Read here. Depending on the information source, modern "unprecedented" warming is an increase of +0.5 to 0.7 degrees Celsius. Despite the hysteria expressed about this increase by the media and alarmists, in both the historical and ancient past there have been warmings that exceeded the modern warming.
Recently, a prominent climate scientist came across a long forgotten study published back in 1973 that documents the large warmings and coolings that took place in China thousands of years ago. As an example, the long ago Shang Dynasty, which had its capital approximately at the red spot on the map, experienced extended warming that was found to be 2 degrees higher than modern temperatures. The Shang dynasty existed at this location from 1400 BC to 1050 BC. (map source here)
Other warming/cooling phases affecting the Chinese civilization were documented to range from 2 to 3 degrees over multiple periods.
“The world climate during the historical times fluctuated. The numerous Chinese historical writings provide us excellent references in studying the ancient climate of China. The present author testifies, by the materials got from the histories and excavations, that during Yin-Hsu at Anyang, the annual temperature was about 2℃ higher than that of the, present in most of the time. After that came a series of up and down swings of 2—3℃ with minimum temperatures occurring at approximately 100 B. C. (about the end of the Yin Dynasty and the beginning of the Chou Dynasty), 400 A. D. (the Six Dynasties), 1200 A. D. (the South Snug Dynasty), and 1700 A. D. (about the end of the Ming Dynasty and the beginning of the Ching Dynasty). In the Han and the Tang Dynasties (200 B. C.—220 A. D. and 600—900 A. D.) the climate was rather warm." [Chu Ko-Chen 1973: China National Knowledge Infrastructure]
Read here. The IPCC claims that modern "unprecedented" global warming has caused glaciers and snowpack to shrink, and mountainous areas to become more arid, thus diminishing/eliminating essential alpine river discharges. Whether it's the Himalayas or other mountainous regions though, the empirical evidence does not support the claims of modern warming being "unprecedented," nor the convenient disappearing of the Medieval Warming and Little Ice Age climates of Mann's 'hockey-stick.'
A new peer-reviewed study by Wolfe et al. found that a Canadian lake's modern water level, which is fed from Rocky Mountain water runoff, is significantly higher than during the Medieval Warming Period and higher than lake levels prior to the extended Medieval span. This is an unequivocal indicator that modern warming is not "unprecedented." (click on image to enlarge)
"A peer-reviewed paper published online today in the journal Geophysical Research Letters shows that drought of Western North America was considerably worse during the Medieval Warming Period than at the end of the 20th century. The paper also shows much more variation and extremes in the drought record over the past 5200 years than since the advent of industrialization and rising CO2 levels in the latter 20th century. The proxy records clearly show no correlation of drought with the claimed steady CO2 levels...""a new 5200-year record of Lake Athabasca water-level variations, which serves as a sensitive gauge of past changes in alpine-sourced river discharge, reveals that western Canadian society has developed during a rare period of unusually abundant water ‘subsidized’ by prior glacier expansion.""[Brent B. Wolfe, Thomas W. D. Edwards, Roland I. Hall, John W. Johnston 2011: Geophysical Research Letters]
Read here. Image source here. (click image to enlarge)
The discredited, bogus 'hockey stick' temperature reconstruction has motivated hundreds to conduct new research on the paleo-climate, utilizing valid scientific and statistical methods. The vast majority of these new studies confirm the anecdotal historical evidence that the Medieval Period was the warmest extended time span over the last 2,000 years.
Velle et al. recently published a peer-reviewed analysis of sediment cores from the Svalbard archipelago in the Arctic. The analysis revealed the Medieval Warming in a polar Arctic area to be approximately 0.3°C higher than modern temperatures.
"Working with two short gravity cores and two long piston cores of sediments obtained from the deepest part of Lake Skardtjorna, Velle et al. reconstructed histories of chironomid types and concentrations over the past 2000 years, which they translated into mean July air temperatures based on a modern mean July air temperature calibration data set...in the words of the two researchers, a "warming that occurred at 1000 to 830 BP," where BP = 2003, that "may correspond to what is known as the 'Medieval Warm Period'." And based on their graphical representation of that record, we estimate that the peak warmth of the MWP (~ AD 1000-1170) was about 0.3°C greater than the peak warmth of the Current Warm Period. [Gaute Velle, Katrine Kongshavn, H. John B. Birks 2011: The Holocene]
Read here. The IPCC and climate alarmists have become well known for their hysterical and failed glacier catastrophe prognostications. To add to the IPCC's growing embarrassment, new research indicates that the Rhône Glacier is currently larger than in previous times, which doesn't lend much credence to their claims of the supposed "unprecedented" warming of the 20th/21st centuries.
Interestingly, due to the glacier's melting, it has actually revealed how warm it really was in the not too distant past - under the glacier were remains of human settlements and forests that are now seeing the light of day, again. Obviously, much to the chagrin of the IPCC's Climategate scientists, the human past has experienced a much warmer climate.
Using novel techniques involving measurement of isotopes Carbon 14 and Beryllium 10, Goehring et al. were able to analyze past glacier growth and shrinkage over the past 11,500 years.
"Until now, scientists have had no accurate way of knowing the long-term history of the glacier. Local records of the ice date back to 1602, and it is clear that the Rhone, like other glaciers in the Alps, has retreated dramatically in the past 150 years. This melting has exposed intriguing clues – remnants of trees from once-forested land, and artifacts of human settlements dating back thousands of years, to times when even more of the land was uncovered and green...the researchers said that their more robust history of the Holocene glacier fluctuations reflects how sensitive glaciers are to small changes in climate...said he was surprised by the evidence of exposure revealed by the isotopes. The amount of Beryllium 10 and Carbon 14 they found "told us that not only were the surfaces exposed for significant periods of time, meaning the Rhone Glacier was smaller than today..." [Brent M. Goehring, Joerg M. Schaefer, Christian Schluechter, Nathaniel A. Lifton, Robert C. Finkel, A.J. Timothy Jull, Naki Akçar, Richard B. Alley 2011: Geology]
Magny et al. utilizing advanced scientific techniques, reconstructed 1,000 years of past summer (July) temperatures for the Swiss Jura Mountains region. Unequivocally, they found that July temperatures during the Medieval Period were significantly warmer than modern summer temps.
"Working at Lake Joux in the Swiss Jura Mountains...employed a multi-proxy approach with pollen and lake-level data to develop a 1000-year history of the mean temperature of the warmest month of the year (MTWA), which was July...based on the Modern Analogue Technique. This work revealed what they describe as an "MWP between ca. AD 1100 and 1320," during which time the MTWA at Joux Lake exceeded that of the 1961-1990 reference period by fully 2.0°C....Thus, it would appear that the peak warmth of the MWP at Lake Joux exceeded that of the CWP at that location by something on the order of 0.4-1.0°C." [Michel Magnya, Odile Peyrona, Emilie Gauthiera, Boris Vannièrea, Laurent Milleta, Bruno Vermot-Desroches 2011: Quaternary Research]
Read here. In peer-reviewed research published by the influential Proceedings of the National Academy of Sciences (PNAS), scientists reconstructed 5,600 years of climate conditions in Greenland. This new reconstruction confirmed the warm and optimum climate conditions of the Medieval Warming and the rapid onset of the frigid Little Ice Age.
In the case of Greenland's flourishing Viking settlements, the climate change to a cold phase meant total destruction of their existing society and settlements.
This new PNAS study totally refutes Michael Mann's entirely bogus 'hockey stick' portrayal of climate being benign and unchanging prior to the 20th century.
"What climate scientists have been able to ascertain is that an extended cold snap, called the Little Ice Age, gripped Greenland beginning in the 1400s. This has been cited as a major cause of the Norse’s disappearance. Now researchers led by Brown University show the climate turned colder in an earlier span of several decades, setting in motion the end of the Greenland Norse...The Vikings arrived in Greenland in the 980s...The arrival coincided with a time of relatively mild weather, similar to that in Greenland today. However, beginning around 1100, the climate began an 80-year period in which temperatures dropped 4 degrees Celsius (7 degrees Fahrenheit), the Brown scientists concluded...“You have an interval when the summers are long and balmy [Editor: yes, Greenland summers "long and balmy" during the Medieval period] and you build up the size of your farm, and then suddenly year after year, you go into this cooling trend, and the summers are getting shorter and colder and you can’t make as much hay. You can imagine how that particular lifestyle may not be able to make it,”...[William J. D’Andreaa, Yongsong Huanga, Sherilyn C. Fritz, N. John Anderson 2011:Proceedings of the National Academy of Sciences]
As so many past studies have documented, the Medieval Warming Period was indeed hotter than our current climate, especially in the extreme north and polar regions, such as Greenland and Iceland. The empirical evidence from past research, using a wide variety of scientific techniques, confirms the anecdotal information that was written in the historical past. A newly published study again confirms both the past scientific efforts and historical writings.
Ran et al. performed a diatom-based reconstruction of sea surface temperatures from waters of northern Iceland. Their analysis found that temperatures were approximately 0.6°C higher during the AD 940-1300 period versus modern temperatures. In addition, a strong solar radiation influence was noted in the data. (click on image to enlarge)
"Ran et al. reconstructed summer sea surface temperature (SST) on the North Icelandic shelf for the period AD 940-2006, based on their high-resolution and precisely dated diatom records, along with the help of "a modern diatom-environmental dataset from around Iceland...In the words of the four researchers, their diatom-based SST record indicates that the sea surface on the North Icelandic shelf "was not as warm during the last century as during the Medieval Warm Period (MWP)." More specifically, they write that "warm and stable conditions with relatively strong influence of the Irminger Current on the North Icelandic shelf are indicated during the interval AD 940-1300, corresponding in time to the MWP," and that "a considerable cooling at ~AD 1300 indicates the transition to the Little Ice Age (LIA) with increased influence of Polar and Arctic water masses deriving from the East Greenland and East Icelandic currents."...they end by stating that "the data suggest that solar radiation may be one of the important forcing mechanisms behind the palaeoceanographic changes."" [Lihua Ran, Hui Jiang, Karen Luise Knudsen and Jón Eiríksson 2011: Palaeogeography, Palaeoclimatology, Palaeoecology]
Read here. Map source here. Wet, cold, stormy, miserable, severe weather can be an indicator of a global cooling climate phase. As past empirical evidence well documents, the climate makes swings from warmer to cooler phases, which impacts local and regional weather patterns.
New research (Griessinger et al.) from China confirms that global cooling can cause weather to become wetter and soggier even in semi-arid areas during the hot summer months of the Northern Hemisphere. (click on images to enlarge)
"Based on correlations they exhibited with climate data, tree-ring δ18O measurements of high-elevation Tibetan junipertrees...state that the 800-year annually-resolved oxygen isotope series they developed reflects long-term variations in Asian summer monsoon (ASM) activity in that part of the world. And this history, as they describe it, reveals an "ASM minimum during the Medieval Warm Period (around 1200-1400) and moister conditions during the Little Ice Age (1400-1900),"...This close but inverse correspondence between centennial-scale precipitation anomalies and similar well-known global temperature anomalies (the MWP, LIA and CWP) provides further evidence for the historical reality of the MWP on the Tibetan Plateau,..." [Jussi Grissinger, Achim Bräuning, Gerd Helle, Axel Thomas, Gerhard Schleser 2011: Geophysical Research Letters]
In Europe's past there have been severe superstorms (category 3 intensity or more) that have struck the Mediterranean coast of Europe. By analyzing sediment cores, Dezileau et al. were able to determine that all the catastrophic storms struck before 1900, primarily during the coldest periods of the Little Ice Age and the onset of the cooler Dark Ages.
The evidence shows that periods of global cooling trends, not global warming phases, are when Europe is at its most vulnerable for Mediterranean superstorms striking.
"With respect to extreme weather events, the authors write that the major question of the day is: "are they linked to global warming or are they part of natural climate variability?"...because "these extreme events are inherently rare and therefore difficult to observe in the period of a human life."...Dezileau et al. assessed "the frequency and intensity of these events during the last 1500 years," as well as "links between past climatic conditions and storm activities."...report they found evidence of four "catastrophic storms of category 3 intensity or more," which occurred at approximately AD 455, 1742, 1848 and 1893...all four of the storms "can be called superstorms."...Dezileau et al. suggest that "extreme storm events are associated with a large cooling of Europe,"..." [L. Dezileaua, P. Sabatiera, P. Blanchemanchec, B. Jolyd, D. Swingedouwe, C. Cassoue, J. Castaingsa, P. Martinezf and U. Von Grafensteing 2011: Palaeogeography, Palaeoclimatology, Palaeoecology]
Read here. Map source here. (click on images to enlarge)
Newton et al. analyzed sediment cores from the Makassar Strait between the Indian and Pacific Oceans and confirmed that the hottest sea-surface temperatures took place some 800+ years ago, during the Medieval Period. These scientists noted that Medieval Warming took place during a solar activity maximum.
"Based on Mg/Ca ratios of the planktonic foraminifer Globigerinoides ruber that they obtained from a sediment core that was extracted from the seabed at the southern end (~5.3°S, 117.8°E) of the Makassar Strait...as they describe it, that "the warmest sea surface temperatures of the past 2000 years occurred between 1000 and 800 years ago," which period, they say, "is broadly coincident with the Medieval Warm Period as reflected in Northern Hemisphere temperature anomaly reconstructions."
"...used to reconstruct surface-water temperature (SST), sea-surface salinity (SSS), and seawater density variability over the past 2000 yr. Maximum SST and SSS occurred at both sites between 850 and 700 yr ago, coinciding with the Medieval Solar Maximum and Medieval Warm Period (ca. 1000–700 yr ago). SST and SSS declined at both locations after 700 yr ago and reached minimum values during the Little Ice Age, between 300 and 100 yr ago." [Alicia Newton, Robert Thunell and Lowell Stott 2011: Geology]
Abrupt and massive climate change, as represented by temperatures, has been a natural phenomenon for eons. Despite the claims of IPCC activists, pundits, celebrities, reporters, and some politicians, our current climate change is not unequivocally unprecedented and accelerating faster than previous occurrences. In fact, as the below charts depict, the current climate change is kind of wimpy compared to its ancestors.
It's important to recognize that scientists within the physical science realm concur that the climate can change abruptly with great severity, and that it has taken place with regularity over the last 10,000 years. Their proof? It's the ice cores pulled from the Greenland ice cap, which reveal incredibly large temperature changes as the graph immediately adjacent reveals. (And the Antarctic ice cores provide even more proof.)
As the experts will tell you, there is absolutely no scientific dispute regarding this historical evidence that was laid down by the climate for thousands of years.
While analyzing the ice core data, the scientists additionally determined several undisputed scientific facts:
1. Temperatures have been both hotter and colder than modern temperatures over the last 10,000 years.
2. There has been a cycle of warmer and cooler temperature swings over the last 10,000 years.
3. The modern increase in temperatures since the Little Ice Age represents #19 in the count of climate change swings over the last 10,000 years.
4. Major temperature swings of at least a 1 degree change may take anywhere from 220 years to 1000+ years before ending.
5. The recent past temperature increase has been both modest (below 1 degree) and relatively slow (750+ years) to warm since the initial plunge to the Little Ice Age levels.
These scientific facts are depicted in the visual representation of ice core data below (click on image to enlarge):
The #1 bar is this chart is that of a warming period that started around 10,000 years ago, lasting 840+ years with a temp increase of 1.23 degrees. The #2 bar represents the subsequent cooling period, which lasted some 850 years with temps cooling a huge 3 degrees. The rest of warm/cool climate change swings are represented all the way down to the present period, which is bar #19. (Each bar lists the associated temperature change and the length of the cooling/warming period, from peak to trough or vice versa.)
The modern bar (#19) is especially revealing. Since the initial plunge of the Little Ice Age temperatures about 750 years ago, the natural warming rebound has yet to even cross the 1 degree finish line that would denote this most recent climate change as a major one. Based on historical, natural precedents that the ice core evidence provides, our modern period should be expecting to reach the 1 degree mark in the near term future, regardless of any human influences - that's what nature and the climate does, naturally.
One final note: the ice core data only extends to 1905. To estimate the temperature change from 1905 to 2010, 'C3' used a really useful graphing service provided by Global Warming Science. Using this invaluable service, we found 4 arctic area weather stations (above 65N) that had fairly complete temperature records from 1905. The chart below is the end result, including a linear trend for the 4 stations: 0.55 degrees per 100 years.
Read here. Scientists analyzing maximum latewood density (MXD) datasets from Scandinavia determine that the Medieval Warming was unprecedented in its duration, at least 100 years in length.
In contrast to the modern era, this study, by Gunnarson et al., revealed that there were similar temperature increases from 1910 to 1940's, and one that started in the late 1990's. Neither of these very short-term warmings have MDX temperature reconstructions exceeding the Medieval Period.
"Working in the same general area, researchers combined these older historical MXD data with "recently collected MXD data covering AD 1292-2006 into a single reconstruction of April-September temperatures for the period AD 1107-2006,".....report "there is a steep increase in inferred temperatures at the beginning of the twelfth century, followed by a century of warm temperatures (ca. 1150-1250)," which falls within the temporal confines of the Medieval Warm Period; and they state that "the record ends with a sharp increase in temperatures from around 1910 to the 1940s, followed by decreasing temperatures for a few decades," after which they indicate that "another sharp increase in April-September temperature commenced in the late 1990s," during what is commonly known as the Current Warm Period. Thus, they say that "the two warmest periods are the mid to late twentieth century and the period from AD 1150-1250," and they emphasize that the temperatures of both of these periods have been so similar that "it is not possible to conclude whether the present and relatively recent past are warmer than the 1150-1250 period."" [Björn E. Gunnarson, Hans W. Linderholm, Anders Moberg, 2011: Climate Dynamics]
Read here. Map source here. (click on images to enlarge)
There are multiple factors that affect both regional and global temperatures, but the most important source of long-term temperature change is solar activity. Using data from the Norwegian Sea and multiple solar proxies, the peer-reviewed research by Sejrup et al. confirms a robust and synchronous correlation between solar activity and temperatures.
Note: This research was conducted and completed without the use of magical "hockey stick" science and statistics, perfected by Penn State University personnel.
"...worked with two sediment cores they extracted from the seabed of the eastern Norwegian Sea, developing a 1000-year proxy temperature record "based on measurements of δ18O in Neogloboquadrina pachyderma, a planktonic foraminifer that calcifies at relatively shallow depths within the Atlantic waters of the eastern Norwegian Sea during late summer," which they compared with the temporal histories of various proxies of concomitant solar activity.....This work revealed, as the seven scientists describe it, that "the lowest isotope values (highest temperatures) of the last millennium are seen ~1100-1300 A.D., during the Medieval Climate Anomaly, and again after ~1950 A.D." In between these two warm intervals, of course, were the colder temperatures of the Little Ice Age, when oscillatory thermal minima occurred at the times of the Dalton, Maunder, Sporer and Wolf solar minima, such that the δ18O proxy record of near-surface water temperature was found to be "robustly and near-synchronously correlated with various proxies of solar variability spanning the last millennium," with decade- to century-scale temperature variability of 1 to 2°C magnitude." [Sejrup, H. P., S. J. Lehman, H. Haflidason, D. Noone, R. Muscheler, I. M. Berstad, and J. T. Andrews 2010: J. Geophys. Res]
Read here. Map source here. (click on image to enlarge)
As coastal elites and MSM reporters remain on the 'stuck-on-stupid' belief that current temperatures are"unprecedented," climate researchers continue to establish a scientific database that documents the unprecedented warmth of the Medieval Warming Period.
The newest addition to the database is a peer-reviewed study by Mullins et al. that reveals the New York region being both warmer and wetter than the present climate.
"Working with two sediment cores extracted from the extreme southern end of Cayuga Lake in central New York researchers "found paleolimnological evidence for the Medieval Warm Period (~1.4-0.5 ka), which was warmer and wetter than today." This evidence included weight percent total carbonate, total organic matter, non-carbonate inorganic terrigenous matter, carbonate stable isotopes, carbon isotope values of total organic matter and fossil types (gastropods, ostracods, bivalves, oogonia) and amounts, all of which were used to interpret past climate based on their relationship to modern climate data for the Finger Lakes region of the state. And to make their findings perfectly clear, they repeat that the "data for central New York suggest a warmer, wetter climate than today."" [Henry T. Mullins, William P. Patterson, Mark A. Teece and Adam W. Burnett 2011: Journal of Paleolimnology]
Read here. A new analysis of Greenland ice cores conclusively identifies the extremes of both the Medieval Warming and the Little Ice Age, represented by a 50-year average temperature measurement. This same measurement identifies the 1950's as a modern peak for the 50-year average, with a subsequent cooling through the mid-1990's.
This peer-reviewed analysis, by Kobashi et al., clearly shows that temperatures and climate exhibit a wide variation, regardless of atmospheric CO2 levels. In fact, these scientists state categorically that there are natural, decadal and century-long oscillations that are driving Arctic regional temperature changes over the past, the present and foreseeable future. These decadal/century periodicity events significantly pre-date human CO2 emission influence. (click on image to enlarge)
"Here, we reconstruct the last 1,000 years of central Greenland surface temperature from isotopes of N2 and Ar in air bubbles in an ice core. This technique provides constraints on decadal to centennial temperature fluctuations. We found that northern hemisphere temperature and Greenland temperature changed synchronously at periods of ∼20 years and 40–100 years. This quasi-periodic multi-decadal temperature fluctuation persisted throughout the last millennium, and is likely to continue into the future.....The data show clear evidence of the Medieval Warm Period and Little Ice Age in agreement with documentary evidence." [Takuro Kobashi · Jeffrey P. Severinghaus · Jean-Marc Barnola · Kenji Kawamura · Tara Carter · Tosiyuki Nakaegawa 2010: Climatic Change]
Read here. Paleo-climate and ocean scientists have relied on a theory to explain pre-historical, ancient and historical sea level changes. Now comes actual empirical evidence from the Mediterranean Sea that casts doubt on the "consensus" science.
Dorale et al. using precise measurement techniques determined that the Mediterranean sea level some 81,000 years ago was significantly higher than the current day level, which is counter to past accepted science.
"Precise measurements of sea level from Mediterranean caves have revealed that about 81,000 years ago the seas stood much higher than previously thought — even higher than today's levels.....now suggests that 81,000 years ago the sea level increased sharply to reach a high-point, roughly one metre above today's level. "At face value this is a very beautiful and solid piece of work," says Wallace Broecker, a geologist and climate scientist..."..."It suggests that, for reasons unknown, the sea level which at the time should have been down some 15 metres instead went up one metre, and then went right back down again within just a couple of thousand years." [Jeffrey A. Dorale, Bogdan P. Onac, Joan J. Fornós, Joaquin Ginés, Angel Ginés, Paola Tuccimei, David W. Peate 2010: Science]
Read here. Map source. (click on images to enlarge)
The IPCC and global warming alarmists have attempted to convince policymakers and the public that modern global warming is unprecedented. In addition, the Climategate scientists claimed that prior climate warming periods only took place in North Atlantic/European regions. Peer-reviewed study after study clearly documents that actual empirical evidence does not support the IPCC and alarmist sceintists claims, as this Chinese data reveals.
"Working with a sediment core extracted from the northern East China Sea...the authors [Li et al.] employed the alkenone paleotemperature index Uk'37...to construct a sea surface temperature history of that region covering the past 3600 years..."the highest temperature was 22.7°C which was recorded at 1.01 cal ka BP," about three-fifths of the way through the Medieval Warm Period...calculate that the peak warmth of the MWP was 2.9°C greater than the mean warmth of the first decade of the 21st century..."[GuangXue Li, XiaoYan Sun, Yong Liu, Torsten Bickert, YanYan Ma 2009: Chinese Science Bulletin]
Read here. Map source (click on image to enlarge). The sad record of failed IPCC and Climategate scientist predictions of global-warming caused disasters continues. Climate alarmists have been predicting that a warming climate will provoke increased flooding, due to a warmer atmosphere holding increased water moisture.
Scientists, Czymzik et al., analyzing 450 years of data from Germany, found the IPCC's increased flooding prediction to be the total opposite of reality. Instead, it was determined that colder climates have a greater frequency of floods.
"...the authors write that "assumptions about an increase in extreme flood events due to an intensified hydrological cycle caused by global warming are still under discussion and must be better verified," while noting that some historical flood records indicate that "flood frequencies were higher during colder periods.....The six scientists determined that the flood frequency distribution over the entire 450-year time series "is not stationary but reveals maxima for colder periods of the Little Ice Age when solar activity was reduced," while reporting that "similar observations have been made in historical flood time series of the River Main, located approximately 200 km north.....As time marches on and as ever more studies of this nature are conducted in Europe and elsewhere, it is becoming ever more clear that the climate-alarmist assumption -- as Czymzik et al. describe it -- of "an increase in extreme flood events due to an intensified hydrological cycle caused by global warming" is simply not correct." [Markus Czymzik, Peter Dulski, Birgit Plessen, Ulrich von Grafenstein, Rudolf Naumann, Achim Brauer 2010; Water Resources Research]
Read here. Fabricated claims by global warming alarmists regarding the frequency and intensity of modern severe weather events has recently seen an uptick as idiot-elites do their thing sans empirical evidence. Despite the MSM pundit fabrications, researchers continue to publish their peer-reviewed findings that clearly indicate current severe weather events are not extraordinary per the past.
The newest research by Stambaugh et al. reveals that historical droughts that occurred in America's corn belt were more frequent, more intense and longer than those that have happened since large industrial/consumer CO2 emissions began.
"...[researchers] used a new long tree-ring chronology developed from the central U.S. to reconstruct annual drought and characterize past drought duration, frequency, and cycles in the U.S. Corn Belt region during the last millennium."....."Of great significance is the fact that the new drought reconstruction indicates that "drought conditions over the period of instrumental records (since 1895) do not exhibit the full range of variability, severity, or duration of droughts during the last millennium.""....."that "three of the top ten most severe droughts occurred within a 25-year period corresponding to the late 16th century." Likewise, they state that "the four longest droughts occurred prior to Euro-American settlement of the region (ca. AD 1850)."....."In fact, the longest drought detected by Stambaugh et al. occurred in the middle of the Medieval Warm Period and, as they describe it, "lasted approximately 61 years (AD 1148-1208)."" [Michael C. Stambaugh, Richard P. Guyette, Erin R. McMurry, Edward R. Cook, David M. Meko and Anthony R. Lupo 2011: Agricultural and Forest Meteorology]
Read here. Map source here. A new peer-reviewed study (Clegg et al.) firmly establishes that modern global warming is significantly less than the global warming experienced in the high latitudes, during the summers of multiple periods over the last 3,000 years. Specifically, historical global warming is still unprecedented, and modern warming is a blip in comparison. (click on images to enlarge)
"The authors conducted a high-resolution analysis of midge assemblages found in the sediments of Moose Lake in the Wrangell-St. Elias National Park and Preserve.....The results of the study are portrayed in the accompanying figure, where it can be seen, in the words of Clegg et al., that "a piecewise linear regression analysis identifies a significant change point at ca 4000 years before present (cal BP)," with "a decreasing trend after this point." And from 2500 cal BP to the present, there is a clear multi-centennial oscillation about the declining trend line, with its peaks and valleys defining the temporal locations of the Roman Warm Period, the Dark Ages Cold Period, the Medieval Warm Period, the Little Ice Age.....and, finally, the start of the Current Warm Period, which is still not expressed to any significant degree compared to the Medieval and Roman Warm Periods." [Benjamin F. Clegg, Gina H. Clarke, Melissa L. Chipman, Michael Chou, Ian R. Walker, Willy Tinner, Feng Sheng Hu 2010: Quaternary Science Reviews]
Read here, here and here. The IPCC and Climategate scientists, such as Michael Mann, teamed up to rid the world of the Medieval Warming Period and the Little Ice Age in an effort to convince the world's politicians and mainstream press that the modern warming was "unprecedented." Literally, Mann and his colleges presented a temperature history that had erased the warming and cooling extremes prior to the modern era.
The result of that effort was two fold: one, the infamous 'hockey stick' portrayal of historical temperatures as being a time of little temperature variation was blatantly contrary to known history and evidence; and two, the recognition by other scientists and a minority of the public that climate science had become the complete victim of the governing elites' political agenda.
Subsequent to the 'hockey stick' revelations of politics and fabricated temperature histories, many scientists pushed harder to examine the historical past, in attempts to reconstruct paleo-climate temperatures and climate.
This new study, by Büntgen et al., was able to identify the significant warming periods and the resultant civilization prosperity of a warmer climate, as represented by the known Roman warming and Medieval periods. The tree rings also identified both the Dark ages and Little Ice Age extreme coolings and the associated disease, famine and death of those natural cold periods.
"Climate variations have influenced the agricultural productivity, health risk, and conflict level of preindustrial societies.....Wet and warm summers occurred during periods of Roman and medieval prosperity. Increased climate variability from ~AD 250 to 600 coincided with the demise of the Western Roman Empire and the turmoil of the Migration Period." [Ulf Büntgen, Willy Tegel, Kurt Nicolussi, Michael McCormick, David Frank, Valerie Trouet, Jed O. Kaplan, Franz Herzig, Karl-Uwe Heussner, Heinz Wanner, Jürg Luterbacher and Jan Esper 2010: Science]
"Der Spiegel presents the most important results, which I myself think are not a surprise. The bulk of the Der Spiegel piece focuses on the hunger and misery precipitated by the climatic cold periods throughout the 2500-year period. One really gets a sense of how temperatures in Europe by no means followed the hockey stick shape proposed by Mann, and went from cold to warm, and vice versa. Numerous other proxies show the same applies globally."
Read here. Map source here. The IPCC Climategate scientists and their AGW alarmist brethren at national climate agencies predicted that global warming would increase precipitation in mountainous regions, thus causing more mud/debris slides. Per a peer-reviewed study of an area of the Swiss Alps, this prediction has failed miserably, like so many.
"The authors note that it has been suggested that global warming may increase the frequency of extreme precipitation events and, therefore, that it may enhance the occurrence of natural mass-movement processes such as debris flows in mountainous regions. In fact, they state in regard to this particular phenomenon that there is a "widely accepted assumption that climatic changes will univocally lead to an increase in event frequency."".....The two Swiss scientists found there were peaks in debris-flow activity "toward the end of the Little Ice Age and in the early twentieth century when warm-wet conditions prevailed during summers in the Swiss Alps," but they say they also observed "a considerable decrease in frequency over the past decades which results from a decrease in the frequency of triggering precipitation events.".....they add that their findings "are in concert with data from Jomelli et al. (2007), indicating that the most recent past (2000-2009) represents the period with the lowest frequency of debris-flow events since AD 1900," which latter decade is touted by climate alarmists as having been the warmest such period of the past millennium or more." [Bollschweiler, M. and Stoffel, M. 2010: The Holocene 20: 907-916]
Read here. Another peer-reviewed study proves the IPCC speculative claim that modern temperatures are "unprecedented" is bogus.
Although the infamous Climategate scientists attempted to force the false "hockey stick" caricature of historical temperatures on the public, the on-going scientific research continues to discover that Medieval Period temperatures were, on average, higher than our present temperatures.
Per a new study, a lake in Switzerland provides evidence from sediment cores that refutes IPCC's propaganda that modern temperatures are warmer than past temperatures. (click on image to enlarge)
"Based on their analysis of fossil chironomids that were identified and quantified in four sediment cores extracted from the bed of Lake Silvaplana in the eastern Swiss Alps, plus a previously developed 101-lake transfer function, Larocque-Tobler et al. constructed a detailed history of that region's mean July air temperature over the last millennium.....it can be seen that the peak mean warmth of the Medieval Warm Period exceeded that of the Current Warm Period by approximately 0.5°C in the case of 20-year averages and 1.2°C in the case of 50-year averages." [Larocque-Tobler, I., Grosjean, M., Heiri, O., Trachsel, M. and Kamenik, C. 2010 Quaternary Science Reviews29: 1940-1949]
Read here. Other than the typical lamebrain MSM reporters (scroll down to Arctic temps "reported" by George Monbiot), just about everyone else knows that NASA completely fabricates modern hot Arctic temperatures from wishful alarmist thinking.
NASA's blatantly, bogus temperatures (lies?) are an attempt to scare the public into thinking the ice sheets of Greenland are quickly melting away because of unprecedented "high" temperatures, including those maximum high temperatures forecasted for the ice sheet this week: an average of a -35°F (yes, minus) for the daily high temps. Obviously, the northern ice sheets are safe despite the bogus NASA and Monbiot Arctic alarmism.
While NASA's computer jocks spend their time and our money on fabricating fake temperatures, real scientists continue to conduct expert scientific research on the Arctic. Their latest peer-reviewed findings confirm a previous study that the Medieval Period experienced Arctic temperatures some 2-3°C higher than modern Arctic temps. Map source here.
"We have generated a ~5,000 year long, decadally-resolved record of summer water temperature from the annually-laminated sediments of Lower Murray Lake on Ellesmere Island in the Canadian High Arctic. The varved sediments of Lower Murray Lake allowed high-resolution sampling and excellent chronologic control of the sedimentary record.....Most strikingly, the alkenone record reveals warm lake water temperatures beginning ~800 AD and persisting until ~1200 AD, with temperatures up to 2-3 deg C warmer than the mean temperature for the past 100 years. This dramatic medieval warm period on Ellesmere Island interrupted a distinct (neoglacial) cooling trend that had begun approximately 2000 years earlier." [D'Andrea, W. J.; Bradley, R. S. 2010]
Read here. The 2010 summer Russian heat wave and resulting forest fires have been claimed to be the result of global warming and climate change. Unfortunately for the AGW alarmists and activist scientists, NASA found these claims to be of little merit.
More importantly, modern heat waves and forest fires in Russia are not unprecedented. These severe weather events happen with some frequency, including the documented severe events of these years (link above for more info):
1298, 1364,1431,1735, 1831, 1839-1841, 1868, 1875, 1885 and 1917
Other than a handful of discredited tree-ring studies, the vast accumulation of scientific evidence indicates that modern warming has not been as great as that experienced during the Medieval Warming span.
Another peer-reviewed research study confirms the unprecedented warmth of the MWP from data collected at a lake on Baffin Island, Canada. (click on images to enlarge)
"Sediment cores collected from Donard Lake, Baffin Island, Canada were analyzed to produce a 1240-year record of average summer temperature for this region based on clastic varve thickness..... And in the words of Moore et al. who did the work, "the most prominent feature of the record is a period of elevated summer temperatures from AD 1200-1375," the peak 10-year mean value of which was approximately 0.9°C warmer than the peak 10-year mean value in the vicinity of 1960 (the highest of the last hundred years), 1.2°C warmer than the peak 10-year mean value in the vicinity of 1980, and fully 2.0°C warmer than the last 10-year value of the record, which was centered on approximately 1987." [Moore, J.J., Hughen, K.A., Miller, G.H. and Overpeck, J.T. 2001.]
IPCC Climategate scientists and alarmists claim that modern temperatures are "unprecedented." In another example of just how bogus this claim is, a new peer-reviewed study documents that eastern Finland's temperatures during the Medieval Warming were significantly warmer and extended over a 700-year span, not just a 25-year span that the modern warming represents. (click on images to enlarge)
"Working with a sediment core from Lake Pieni-Kauro in eastern Finland, Luoto and Helama identified and quantified various midge assemblages that were dominated by chironomids, after which they reconstructed a 1500-year history of mean July air temperature from the Finnish multi-lake calibration model of Luoto (2009). The results, shown in the accompanying figure, delineate a Medieval Warm Period stretching from about AD 580 to 1280, the peak temperature of which was approximately 0.3°C greater than the peak temperature at the end of the record, which concludes near the end of 2008. [Luoto, Tomi P. and Helama, Samuli 2010]
'Big Green' and its comrades have proven themselves capable of some the most outlandish lies in their incessant promotion of global governance, regulation and taxation of CO2 emissions. Possibly the biggest of lies is the one that today's modern temperatures are "unprecedented," never before warmer.
This big lie is the linchpin for all the associated hysterical, non-empirical, over-the-top, catastrophic predictions that are made by Big Green. Of course, when the actual, empirical, scientific data is actually considered, the big lie of "unprecedented" is shown to be a blatant falsehood.
As the graphs below reveal, there has been a general decline in polar temperatures over the last 10,000 years. Modern temperatures at both poles are well below their historical peaks.
Simply put, this means both humans and polar bears survived and adapted to warmer temperatures in the recent geological past. In addition, ice sheets outlasted extended periods of significantly higher temperatures in the past. (click on images to enlarge)
The other lie that the empirical evidence exposes as pseudo-science is that CO2 is the primary driving force of climate and temperature change. The ice core evidence is a stunning record of climate and temperature changing regardless of CO2 levels. Obviously, there are other natural forces in play that are the primary "climate disruptors."
That's not to say that human CO2 emissions have no part in modern warming, but it is more likely that a trace gas, like CO2, only has a trace affect on global temperatures and climate.
Notes: The average daily Vostok temperature (1958-2010) is the 2010 data-point for the Antarctica chart. The 2010 Greenland Summit temperature data point is average temperature of recent January through December monthly temperatures (added for modern context). The light gray columns in both charts represent CO2 levels, with 2010 estmated level (added for modern context) being the black column on far right.
YBP (years-before-present) figures were adjusted accordingly with use of year 2010 as end point.
Read here and here. Fredrik Charpentier Ljungqvist, a Stockholm University scientist recently published a peer-reviewed study that found there were previous warming periods that produced a warmer climate than our current climate, over the past 2,000 years . As a followup to that study, Ljungqvist has published additional information for the past 1,200 years that examines paleo-reconstructed temperatures for specific Northern Hemisphere regions.
This new data clearly reveals that both the Medieval Warming and the Little Ice Age cooling were significant climate events across the entire northern portion of the globe. In the majority of regions, modern temperatures are yet to reach the level and extent of the MWP.
"The presently available palaeotemperature proxy data records do not support the assumption that late 20th century temperatures exceeded those of the MWP in most regions.....Previous conclusions (e.g., IPCC, 2007) in the opposite direction have either been based on too few proxy records or been based on instrumental temperatures spliced to the proxy reconstructions. It is also clear that temperature changes, on centennial time-scales, occurred rather coherently in all the investigated regions – Scandinavia, Siberia, Greenland, Central Europe, China, and North America.....Assumptions that, in particular, the MWP was restricted to the North Atlantic region can be rejected."
This new data, combined with his other recent research, establishes without any doubt the existence of substantial climate change prior to 20th century's large emission of CO2. This research completely invalidates the UN's IPCC attempt to falsify historical climate change via the Climategate team of scientists. (click on images to enlarge)
Note: Original graphs had instrumental temperatures superimposed on top of proxy reconstruction during 20th century period. The instrumental data was removed and a reconstruction of the proxy reconstruction was done in order to make them visible - our re-do is close enough for NASA/GISS government work. ;-)
Read here. Map source here. Using sediment cores from lakes, researchers identified distinct periods of climate change, including the Dark Ages, Medieval Warming Period and the Little Ice Age. This peer-reviewed study, like so many, is contrary to the speculative comments by IPCC Climategate scientists who claimed that the MWP was only a northern European phenomenon.
"...the authors measured a number of sediment properties, among which were sulfur content and coarse mineral grains, the former of which served as a proxy for paleo-Asian summer monsoon activity and the latter of which served as a proxy for paleo-Asian winter monsoon activity. This work revealed the presence of a cold/dry interval stretching from AD 1 to 750, a warm/humid interval stretching from AD 750 to 1200, and another cold/dry interval stretching from AD 1200 to the present, which periods they associated, respectively, with "the Dark Ages Cold Period, the Medieval Warm Period and the Little Ice Age ." [Yamada, K., Kamite, M., Saito-Kato, M., Okuno, M., Shinozuka, Y. and Yasuda, Y. 2010]
Read here. Climate alarmist scientists and their computer models have predicted that global warming will cause multiple species to become extinct. Like all global warming predictions emanating from the IPCC Climategate science, this one also does not hold up to actual scientific scrutiny.
Scientists examined past significant global warming periods and discovered that the excessive and extended warmth of those periods did not cause species to die out.
"The first period they examined was the Eocene Climatic Optimum (53-51 million years ago), during which time the atmosphere's CO2 concentration exceeded 1200 ppm and tropical temperatures were 5-10°C warmer than modern values.....The second period they examined consisted of two rapid-change climatic events in the Holocene -- one at 14,700 years ago and one at 11,600 years ago -- during which times temperatures increased in the mid- to high-latitudes of the Northern Hemisphere by up to 10°C over periods of less than 60 years.....the authors note that "at no site yet studied, anywhere in the world, is there evidence in the fossil record for large-scale climate-driven extinction during these intervals of rapid warming." On the other hand, they report that extinctions did occur due to the cold temperatures of the glacial epoch, when subtropical species in southern Europe were driven out of their comfort zone." [Willis, K.J., Bennett, K.D., Bhagwat, S.A. and Birks, H.J.B. 2010]
Read here. Map source here. Numerous temperature reconstructions indicate that during the Medieval centuries, two distinct warming intervals happened. New research from a Scottish loch's sediment core analysis identified the two separate, extended warming periods between 900 and 1600AD.
In addition, the new peer-reviewed research clearly reveals the wide climate variation experienced prior to the large industrial CO2 emissions of the 20th century. The modern warming was found not to be unusual or out of the ordinary. (click on image to enlarge)
"“The Loch Sunart reconstruction for the late MCA suggests temperatures from AD 916 to 1035 were similar to those recorded over the late twentieth century.”..... Cage and Austin [Cage, A.G. and, W.E.N. Austin. 2010] point out “perhaps the most distinctive feature of the Loch Sunart temperature record is the short-lived event between AD 1540 and1600, which is characterized by a very abrupt warming transition at AD 1540. This period had an average temperature anomaly of 1.1ºC above the long-term mean, which is higher than most of the 20th century and the late MCA.”....."“The Loch Sunart temperature reconstruction exhibits a gradual cooling trend that continues from AD 1608 to 1941, with the coldest temperature anomalies (~0.75ºC) of this period occurring between the early 1930s and 1940s.” So in the last 400 years, the sea bottom of Loch Sunart cooled, the coldest period over the past 400 years occurred 70 years ago, and then the water warmed up to levels that were typical during the beginning of the 400-year period."
Read here and here. Map source here. A peer-reviewed study utilizing high resolution data from a peat bog sediment core, analyzes 6,000 years worth of a temperature proxy. The researchers determined that both Roman and Medieval Periods experienced temperatures that were significantly higher than those of the current period. (click on image to enalrge)
"Working with cores extracted from a peat bog west of Jinchuan, China the authors developed "a 6000-year high-resolution δ18O record of peat plant cellulose," which they interpret as "reflecting changes in regional surface air temperature." And from their results, which are depicted in the figure [adjacent], it can be seen that the Medieval Warm Period (which was preceded by the Dark Ages Cold Period and followed by the Little Ice Age) was considerably warmer than the Current Warm Period (which followed the Little Ice Age) has been to date"
Read here. Map source here. Another peer-reviewed study provides high resolution evidence that the world's climate is impacted by an oscillation that occurs approximately every 1,500 years. This oscillation produces rapid climate change, which most likely explains the global warming rebound experienced since the Little Ice Age.
"On the southern coast of the English Channel, Billeaud et al. (2009) studied offshore-derived sediments in the macrotidal setting of Mont-Saint-Michel Bay, France, where they conducted a high-resolution sequence stratigraphy analysis of the intertidal to subtidal wedge, utilizing juvenile shells, peat and organic-rich bulk sediment.....The work revealed that "rapid climate changes, with ~1500-year periodicity, are recorded in the sedimentary successions.....Such results add to the overwhelming evidence provided by other paleoclimate records that have shown, in their words, that "Holocene climate was punctuated by widespread cooling events, recurring every ~1500 ± 500 years (Bond et al., 1997; Bianchi and McCave, 1999; Broecker, 2000; Mayewski et al., 2004; Debret et al., 2007; Allen et al., 2007)."...And since this periodicity suggests that the world was fully ripe for a recovery from the last of these coolings (i.e., the Little Ice Age), 20th-century global warming is seen to be neither unusual, unnatural nor unprecedented..."
Read here. Peer-reviewed research documents the glacier retreat that happened during the Medieval Warming period for the Antarctica peninsula area. Despite Climategate scientists and alarmists claims, this evidence confirms that Antarctica (and the Southern Hemisphere) experienced the climate change of the Medieval era.
"Hall et al. examined organic-rich sediments exposed by recent retreat of the Marr Ice Piedmont on western Anvers Island, where glaciers have been undergoing considerable retreat in response to the well-documented warming of the Antarctic Peninsula..... This work revealed, in their words, that "peat from the overrun sediments dates between 707 ± 36 and 967 ± 47 cal. yr B.P.," which led them to conclude that "ice was at or behind its present position at ca. 700-970 cal. yr B.P," which they interpret as implying that "the present state of reduced ice on the western Antarctic Peninsula is not unprecedented," which means that this period was at least as warm as, or likely even warmer than, the peak warmth of the Current Warm Period."
Read here. Map source here. For eons, Earth's climate and temperatures have changed in a cyclical pattern. In a peer-reviewed study, researchers analyzed a cave speleothem that produced a 17,000 year temperature record. The results clearly show that the climate changes naturally, and significantly, while atmospheric CO2 levels remained at levels well below current levels. They also confirmed that Roman and Medieval period temperatures equaled or exceeded modern temperatures.
"Working with stalagmite SV1 from Grotta Savi -- a cave located at the southeast margin of the European Alps in Italy.....This work revealed -- among several other things -- the occurrence of the Roman Warm Period and a Medieval Warm Period.....the five researchers say they were "characterized by temperatures that were similar to the present," while with respect to the Roman Warm Period, they say its "temperatures were similar to those of today or even slightly warmer.....we have here yet another example of the millennial-scale oscillation of climate that has characterized the earth throughout glacial and interglacial periods alike; and we note that it provides three good examples of times when temperatures were equally as warm as they are presently, or even warmer, in spite of the fact that the air's CO2 content was much lower at those earlier times than it is today."
Read here and here. A new study reconstructs 2,000 years of temperature variation from 30 datasets. The authors eliminated the discredited data and techniques utilized by Michael Mann (of Climategate fame) for multiple studies, and also used by his close paleo research comrades. For example, this study totally avoids the bristlecone pine and foxtail pine data that so miraculously produced the fake hockey-stick blades of temperatures in the 20th century.
This new study's findings demonstrate that climate change has been very active over 2,000 years, with pronounced changes in temperature being one of the results. This past climate change and temperature variation happened in a atmosphere of low CO2 levels. These results also reveal Roman and Medieval temperatures that exceed modern temperatures derived from the same 30 datasets. (click on image to enlarge)
This chart shows the modern global warming, as do so many paleo studies, but confirms that both warming and cooling are natural cyclical events.
Read here. Map source here. Brand new peer-reviewed study that analyzes subfossils from a Swiss lake confirms what hundreds of previous peer-research have found: that the Medieval Warming had temperatures significantly warmer than modern ones.
"Thousand years of climate change reconstructed from chironomid subfossils.....Based on their analysis of fossil chironomids (non-biting midges) -- which were identified and quantified in four sediment cores extracted from the bed of Lake Silvaplana -- the authors constructed a detailed history of that region's mean July air temperature.....Larocque-Tobler et al. report that "at the beginning of the record, corresponding to the last part of the 'Medieval Climate Anomaly' (here the period between ca. AD 1032 and 1262), the chironomid-inferred mean July air temperatures were 1°C warmer than the climate reference period (1961-1990)," which would also make them warmer than most subsequent temperatures as well. And in looking at their graphs of 20- and 50-year running means, it can be seen that the peak mean warmth of the Medieval Warm Period exceeded that of the Current Warm Period by approximately 0.5°C in the case of 20-year averages and 1.2°C in the case of 50-year averages."
Read here. Map source here. Japanese scientists working with historical data and documents determine that the extended Medieval Warming had temperatures exceeding current temps by at least one-half degree in Kyoto. Their research also confirms that the Medieval Warming was global in nature, not just a northern Europe climate condition as speculated by IPCC Climategate scientists.
"The authors investigated documents and diaries from the ninth to the fourteenth centuries to supplement phenological data series pertaining to the flowering of Japanese cherry trees in Kyoto, Japan, "to improve and fill gaps in temperature estimates based on previously reported phenological data," after which they "reconstructed a nearly continuous series of March mean temperatures based on 224 years of cherry flowering data, including 51 years of previously unused data, to clarify springtime climate changes.".....The resulting temperature reconstruction "showed two warm temperature peaks of 7.6°C and 7.1°C, in the middle of the tenth century and at the beginning of the fourteenth century, respectively," and they say that "the reconstructed tenth century temperatures are somewhat higher than present temperatures"...[Yasuyuki Aono, Shizuka Saito 2009: International Journal of Biometeorology]
Read here. Map source here. More research from China confirms Medieval temperatures were significantly warmer than current ones. The study also provides direct evidence that the Medieval Warming was a global phenomenon, not just a European regional climate condition, as the IPCC speculates.
"...the authors extracted cores of peat from a location close to Hani Village, Liuhe County, Jilin Province, China; and they used them to develop, as they describe it, "a peat cellulose δ18O temperature proxy record proximately existing for 14,000 years.""....."Their efforts revealed, first of all, that the MWP had indeed held sway on the Chinese mainland over the period AD 700-1400, peaking at about AD 900......they say MWP temperatures were as much as "0.9-1.0°C higher than modern temperatures "....."with respect to the last 14,000 years, Hong et al. write that "sudden cooling events, such as the Older Dryas, Inter-Allerod, Younger Dryas, and nine ice-rafted debris events of the North Atlantic are almost entirely reiterated in the temperature signals of Hani peat cellulose δ18O."....."indicating that the recurring warming and cooling did indeed occur "outside the European region" and that it truly was "a common phenomenon.""
Read here. Map source here. Those "wild and crazy" Norwegians decided to conduct some home-grown, intimate fjord research. Their up close and definitive findings? Amazingly, they discovered temperatures appear to oscillate from warm-to-cold-to-warm over extended periods, naturally.
Isn't that just incredibly, freaking amazing? (Are leftists/Marxists/liberals/progressives/Democrats aware of this yet?)
"Just as has been discovered numerous times and throughout the entire world, northern Norway has experienced alternating multi-century periods of relative cold and warmth over prior millennia. And this pervasive natural phenomenon appears to be totally sufficient to explain 20th-century warming (there has been no more so far this century) without any need to invoke the help of the greenhouse effect of CO2 or any of the atmosphere's other greenhouse gases."
Read here. Scientists confirm that Northern Hemisphere temperatures during the Medieval Period exceeded those of recent years of the 20th and 21st centuries. The Greenland ice sheet scientific evidence is clear about this, as the chart depicts. (click on image to enlarge)
"The authors say their data "show clear evidence of the Medieval Warm Period and Little Ice Age in agreement with documentary evidence," and those data clearly show that the Medieval Warm Period was at times considerably warmer than the Current Warm Period has been to date, and that even the Little Medieval Warm Period was considerably warmer than it was over the last decades of the twentieth century, as well as the first decade of the 21st century. Thus, there is no compelling reason to believe that the 20th-century increase in the air's CO2 content (a 100-ppm rise above what it was during the warmer Medieval Warm Period) was the cause of 20th-century global warming, especially when climate alarmists claim that such warming, when it occurs, should be most evident and earliest expressed in high northern latitudes..."
Read here. It's amazing what you learn from reading blogs. I had no idea that Hawaii once had glaciers (Hawaii?). But thousands of years ago, during the last glaciation, Hawaii's highest peaks sported glacier ice. And, this glacier ice's retreat and surging during the end of the glaciation age left clues that natural Atlantic Ocean current oscillations were the primary factor affecting the tropical Pacific - not the trace gas CO2.
"However, the new research found that the glacier on Mauna Kea began to re-advance to almost its ice age size about 15,400 years ago. That coincides almost exactly with a major slowdown of what scientists call the Atlantic meridional overturning circulation, or AMOC, in the North Atlantic Ocean.....But scientists have found that the AMOC does more than just keep northern Europe habitable. Its effects can extend far beyond that...“The new data from Mauna Kea, along with other findings from geological archives preserved in oceans and lakes in many other areas, show that the decline of the AMOC basically caused climate changes all over the world,” Clark said. “These connections are pretty remarkable, a current pattern in the North Atlantic affecting glacier development thousands of miles away in the Hawaiian Islands...“The global impact of the AMOC changes,” Clark added, “was just massive.”"
Read here. As everyone knows, regions of Europe, including parts of Russia, experienced an uncomfortable heat wave for several weeks during the summer of 2010. But how about a heat wave and drought that lasted for several months? Well, certainly not in this century, nor during the late 20th century when there was a huge growth in CO2 emissions. But in 1540, there was a European heat wave that was truly unprecedented.
"According to Buisman’s recent findings, the year 1540 was one with an even more severe summer than was 2003. All over Europe, the heatwave lasted, off and on, for seven months, with parched fields and dried up rivers, such as the Rhine. People in Paris, France could walk on the river bed of the Seine without getting their feet wet."
Read here. Map source here. Climate scientists have previously proposed that a 1,500 year oscillation driven by solar activity changes affects the climate, causing periodical warming and cooling cycles. A new study analyzing lake sediment cores from Bolivia confirms the existence of the approximate 1,500 year cycle.
"The five researchers report that their work "shows clear evidence of millennial-scale climate variation between ~60 and 20 ka BP," which was driven by variations in the degree of regional wetness; and they say that this climatic oscillation is well correlated with the stadial/interstadial oscillation of the North Atlantic region. More specifically, they write that "the correlation between the Lake Titicaca and NGRIP records suggests that the major cold periods in the North Atlantic region were synchronous with wet periods on the Altiplano.".....And this combined set of findings suggests that the approximate 1500-year climatic oscillation that alternately brings century-long periods of relative cold and warmth to the Northern Hemisphere impacts the hydrologic climate of the Southern Hemisphere on approximately the same time scale."
Read here. Much to the consternation of the habitual deceivers of the IPCC paleo-climate scientist community, new research keeps piling up confirming the global extent of the Medieval Warming, and its unprecedented, huge climate-change impact. Adding insult to injury to the warming alarmists, the Medieval Global Warming was beneficial by ending the severe weather events that had led to the massive floods during the colder periods.
""In an attempt to determine the environmental origins of extreme flooding events throughout the southwestern United States, according to the author, "paleoflood records from nineteen rivers in Arizona and southern Utah, including over 150 radiocarbon dates and evidence of over 250 flood deposits, were combined to identify regional variations in the frequency of extreme floods," .....The frequency of extreme floods also increased during the early and middle portions of the first millennium AD, many of which coincided "with glacial advances and cool, moist conditions both in the western U.S. and globally." Then came a "sharp drop in the frequency of large floods in the southwest from AD 1100-1300," which corresponded, in her words, "to the widespread Medieval Warm Period, which was first noted in European historical records." With the advent of the Little Ice Age, however, there was another "substantial jump in the number of floods in the southwestern U.S.," which was "associated with a switch to glacial advances, high lake levels, and cooler, wetter conditions.""
Read here. Our modern world is experiencing natural climate change, but scientists are now telling us that it doesn't rival the destructive force of ancient climate change that took place during Medieval times.
When true unprecedented climate change occurs, it can be devastating to cultures and civilizations that are not prepared to adapt to different environmental conditions.
In the case of the Central American Mayans, their civilization was destroyed because they chose to follow the hope of mitigation, through human sacrifice and prayer to their gods, instead of pursuing the practical adaptation needed to survive the natural Medieval Warming drought conditions.
How bad was the climate change for the Mayans during the Medieval Warming period?
"Escobar et al. state that their findings "confirm the interpretations of Hodell et al. (1995, 2007) and Curtis et al. (1996) that there were persistent dry climate episodes associated with the Terminal Classic Maya Period." In fact, they find that "the Terminal Classic Period from ca. AD 910 to 990 was not only the driest period in the last 3,000 years, but also a persistently dry period." And in further support of this interpretation, they note that "the core section encompassing the Classic Maya collapse has the lowest sedimentation rate among all layers and the lowest oxygen isotope variability.".....that "double whammy" of persistent warmth and persistent dryness appears to have been just a bit too much for the Mayans of that trying time to endure.""
Read here. One of the major stuck-on-stupid positions that global warming alarmists claim is that only human CO2 increases cause climate change. This idiotic stance eventually resulted in the bogus hockey-stick study that the world's preeminent statisticians found to be so....well....really bogus. The hockey-stick of course purported to show that no climate changes had occurred over the last 1,000 years until the late 20th century. This idiocy became so apparent that even the IPCC retired the hockey-stick to barely a footnote in its last report.
In spite of the bogus hockey-stick, researchers across the world kept working to better understand past climate change. Another study just released has found that the arid central Asia (ACA) region has had significant climate change over the last 1,000 years during periods of low, unchanging CO2 levels.
"The nine researchers report that the effective moisture (precipitation) in the ACA has a generally inverse relationship with the temperature of the Northern Hemisphere, as portrayed by Moberg et al. (2005), China, as portrayed by Yang et al. (2002), and Central Asia, as portrayed by Esper et al. (2007). That is to say, as they describe it, the "wet (dry) climate in the ACA correlates with low (high) temperature." And stating it in yet another way, they indicate that the ACA "has been characterized by a relatively dry Medieval Warm Period (MWP; the period from ~1000 to 1350 AD), a wet little Ice Age (LIA; from ~1500-1850 AD),"....."which cooling was brought about by the gradual demise of the Medieval Warm Period, which in turn speaks volumes about the great significance of that centuries-long period of much-lower-than-present atmospheric CO2 concentration but of equivalent or even greater warmth than that of the Current Warm Period, which ultimately suggests that the 20th-century increase in the air's CO2 content may have had little, or maybe even nothing, to do with 20th-century global warming"..... and [finally] "a return to arid conditions [from warming] after 1850 AD," which has been slightly muted..."
Read here. Global warming alarmists and agenda-driven pundits frequently spread the meme that global warming will cause more wars, leading to all sorts of imagined scenarios of mayhem, destruction and death later this century and next. Is there any actual empirical evidence backing these more-war claims up? Nope.
In a new peer-reviewed study, researchers examine the empirical evidence and find the claims of retired, fat- assed admirals and generals (real and the armchair variety) to be without merit. Surprised?
"In their conclusions, the authors state “We present some evidence that periods with lower temperatures in the pre-industrial era are accompanied by violent conflicts”, consistent with what others had found in China. Furthermore, they note “If anything, lower temperatures imply violence, and this effect is much weaker in the modern world than it was in pre-industrial times. This implies that future global warming is not likely to lead to (civil) war between (within) European countries.”.....Another popular claim about global warming is once again not supported by what has been observed for centuries – sound familiar?"
Blue/green colors indicate a low correlation between high temperatures and violence. Red reveals the high correlation regions.
Of course, per the evidence, Turkey and the Balkans appear to have a strong correlation with warmth and war. Or, is that a correlation between a certain religion and war/terrorism? And what about Iceland? Yep, them damn Vikings and their distant relatives were pretty frisky during the Medieval Warming until the icy depths of the Little Ice Age finally put Iceland and Greenland back in the deep freezer.
Read here. In a new peer-reviewed study, Russian scientists confirmed that floodplain areas were more widely populated during periods of lesser precipitation (snow and rain). These lesser precipitation regimes occurred during warming periods, with the Medieval Warming being the most significant, not the current warming.
"In a study of the Upper Volga and Zapadnaya Dvina Rivers of Russia, Panin and Nefedov documented "the geomorphological and altitudinal positions of [human] occupational layers corresponding to 1224 colonization epochs at 870 archaeological sites in river valleys and lake depressions in southwestern Tver province,".....The two Russian researchers report finding that "low-water epochs coincide with epochs of relative warming, while high-water epochs [coincide] with cooling epochs," because "during the climate warming epochs, a decrease in duration and severity of winters should have resulted in a drop in snow cover water equivalent by the snowmelt period, a decrease in water discharge and flood stage, and a decrease in seasonal peaks in lake levels,".....And this relationship clearly implies that the current level of warmth in the portion of Russia that hosts the Upper Volga and Zapadnaya Dvina Rivers is not yet as great as it was during the AD 1000-1300 portion of the Medieval Warm Period."