C3

Despite July's Jump In Global Temperatures, Globe Is Still Cooling Over Past 8+ Years

(click on image to enlarge)

Per NOAA, there was a +0.05°C increase in the temperature anomaly over the June 2023 reading.

That means there has been an increase of +0.23°C since July 2022.

In comparison, that 12-month increase pales to the 12-month increase of 0.71°C for February, 1995; the +0.54°C increase for December 1939; and the July 1987 +0.33°C jump

Further analysis of NOAA global temperature dataset confirms that the planet remains in a slight cooling trend over the last 104 months (8.7 years) during a period where atmospheric CO2 levels surged by another 21ppm.

The end result is a negative correlation (-0.030) between CO2 and NOAA temperature anomalies from December 1, 2014 through July 2023. In fact, the weak correlation between these two variables stretches back 10 years to June 2013.

This result completely lays waste to the greenhouse gas 'hopium' that CO2 is a "control knob" that policymakers and scientists can twist and turn to manage and stabilize the climate.

If CO2 is not responsible for the recent warming in 2023, then what are the factors involved that increased temperatures in July and likely will continue to do so in the near future?

This article by a well known climate scientists provides a detailed summary of all the climate factors that are driving 2023 temps up. (Beware, the science is complicated, which reflects the complexities involved within the non-linear and chaotic world climate. And light-years more complicated than the simplistic belief that CO2 is some sort of a "control knob" for achieving climate stability.)

Additional global and regional temp charts.

Notes: Excel used for all calculations and plots. Sources: Global temp anomalies & CO2 levels.

2023 Hawaii Wildfires & Drought: Did CO2 Cause It To Rain Less On The Island of Maui?

In our first article about the recent Maui wildfires, we addressed the issue of whether "global boiling" climate change (aka global warming) due to CO2 growth was the cause of the devastating fires.

Per the NOAA empirical temperature data for Maui, the short answer is that CO2-induced global warming was not the culprit.

Besides the claim that Maui's temperature must have increased due to higher levels of atmospheric CO2, there is also the claim that the growth of CO2 in the atmosphere is to blame for the recent lack of Maui's rainfall.

Not surprisingly, the factual Kahului, Maui empirical evidence from NOAA scientific research does not support that claim either.

This chart plots Maui's monthly precipitation anomalies (monthly amounts above and below normal) and the twelve-month moving average of global atmospheric CO2 ppm levels. (Click on chart to enlarge.)

Visually, there does not appear to be any relationship between CO2 and rain.

And the statistics confirm that the visual intuitiveness is correct.

There is no cause and effect relationship (a R² that essentially is zero) between CO2 and precipitation anomalies over the extended period from 1954 through July 2023.

In addition, there is the claim that the current Maui drought, due to low precipitation levels, is unique, even historically unprecedented, due to recent "climate change".

For most people, the island of Maui is considered a lush paradise. But instead of that perception, in reality, many areas of Maui actually have the characteristics of a dry climate.

Historically for Kahului, Maui, its average annual rainfall of 16.6 inches is 4 inches less than that of Flagstaff, Arizona, which is considered a semi-arid climate. And the Caribbean island of Puerto Rico, in comparison, has an annual precipitation amount some 43 inches greater than Kahului, Maui. (The wildfire devastated town of Lahaina is located in an area even drier than Kahului.)

Maui has a yearly wet-season and a dry-season, each lasting approximately 6 months. During the dry-season (May–October), the rainfall falls to well below 1 inch monthly during the warmer spring and summer months.

The above chart includes a six-month average plot (dark blue) that reveals the seasonal precipitation cycle.

Note that the chart plots three distinct time spans of precipitation anomalies (the gaps in months/years are due to the absence of climate records for those months and years).

However, each time span reveals the seasonal cycle as well as extended periods of below-normal rainfall.

This next chart specifically compares the precipitation anomalies for Kahului from the period of January 1905 through July 1909 versus the period of January 2019 through July 2023.

(click on to enlarge)

Both of these time spans are considered drought periods with below-normal rainfall.

As shown on the chart, the plots of the six-month and 36-month running averages match very closely for each time span. In addition, the current period ending in July 2023 had an average monthly rainfall of 1.2 inches versus 1.1 inches for the 1905–1909 average.

Conclusions: Per the evidence, atmospheric CO2 levels do not have an impact on Maui's central-western region's precipitation amounts; the historical rainfall record establishes that the western and central parts of Maui are a dry climate prone to droughts due to low annual rainfall amounts; and, the current shortfall of precipitation is neither unique nor unprecedented in the least.

For explanations on the causes of the Maui wildfire disaster, read this article, this article, this article, and this article; and this research paper regarding Hawaii droughts.

Note: Source of precipitation data. Excel used for all calculations and the plotting of charts. NOAA's climate records for Maui Hawaii have multiple gaps in monthly data. The months with no climate data were not utilized in any calculations or plots. Lahaina, Maui does not have a NOAA weather/climate station. Instead NOAA relies on the climate station located at the Kahului Airport. Precipitation & temperature monthly averages are very similar: Lahaina and Kahului. Explanation of climate for Hawaii's multiple islands.