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climate-debate

The Holocene CO2 Dilemma

by R. Hannon, June 2023, in WUWT

This post evaluates the relationship of global CO2 with regional temperature trends during the Holocene interglacial period. Ice core records show that CO2 is strongly coupled with local Antarctic temperature and slightly lags temperature over the past 800,000 years (Luthi, 2008). Whereas the emphasis has been on CO2 and temperature lags/leads, this study focuses on Holocene millennium trends in different latitude-bounded regions.

The Contrarian Antarctic

The Holocene is fortunate to have hundreds of proxy records analyzed by Marcott, 2013, and more recently Kaufman, 2020, to establish regional and global temperature trends. The Holocene interglacial occurs approximately during the past 11,000 years. In general, global temperature trends from proxy data show a Holocene Climatic Optimum (HCO) around 6000 to 8000 years ago and a subsequent cooling trend, the Neoglacial period, culminating in the Little Ice Age (LIA). The global mean temperature is comprised of regional trends that tend to have a concave down appearance during the Holocene shown in Figure 1a.

The exception is the Antarctic shown in red which has a concave up shape. The Antarctic reached an early Holocene Climatic Optimum between 9000 to 11000 years ago. While global and most regional temperatures were warming, Antarctic cooled to a minimum around 8000 years ago. While global and other regions show progressive cooling during the Neoglacial, the Antarctic was flat and erratic. This contrary Antarctic temperature behavior during the Holocene has also been noted by Andy May here.

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Observations

Climate change is routinely claimed to be largely controlled by greenhouse gases, especially CO2. This was concluded, in part, by the strong relationship between CO2 from Antarctic ice core bubbles and local Antarctic temperature trends. While CO2 mimics Antarctic temperatures very well, ninety percent of Earth’s surface temperature trends do not demonstrate a positive correlation to CO2 during the Holocene. Arctic and Northern Hemisphere temperatures become cooler during increasing CO2 levels. Tropical proxy temperatures don’t seem to be influenced by CO2.

Model simulated temperatures which are strongly influenced by CO2 do not accurately history match Holocene global proxy temperatures and tend to largely reflect Antarctic trends. The fact that CO2 correlates well to Holocene temperatures for only the Antarctic, or <10% of our planet’s surface, yet CO2 is considered as the dominant influence on climate change is a scientific dilemma.

Download the bibliography here.

climate-debate

Why A Strong El Niño In 2023 Is Unlikely

by R. Cutler, May 25, 2023 in ClimateChangeDispatch

Global warming completely stopped in 2018. Temperatures will likely remain steady until 2025 and may decline slightly by 2030.

A strong El Niño in 2023 is unlikely.

I’ll explain all of my predictions — after we hear from the experts. [emphasis, links added]

NOAA recently predicted a 55% chance of a strong El Niñoin late 2023.

The World Meteorological Organization (WMO) threw more fuel on the fire when it announced, “There is a 98% likelihood that at least one of the next five years, and the five-year period as a whole, will be the warmest on record.”

Obviously, the MSM had a field day with this. Take for example this headline from USA Today: “Scientists warn an El Niño is likely coming that could bring scorching heat to Earth.”

Rather than taking the well-worn path of pointing out flaws in the predictions of NOAA, the IPCC, or the WMO, I’ll instead show how the sun is likely responsible for almost every detail in global temperaturesover the last 125 years, and that it is also responsible for triggering strong El Niños.

Two empirical, or black-box models were created to predict global temperature. The first model uses solar magnetic field data from the Wilcox Solar Observatory (WSO).

The second model uses sunspot data from WDC-SILSO, the Royal Observatory of Belgium, Brussels. Both predictions will be compared to global temperature anomaly data from NOAA.

Solar magnetic field data collection began in 1976. The complete WSO dataset can be viewed in a single graphic, often referred to as a butterfly diagram.

It looks complicated, but it’s really not. It’s just a plot of solar magnetic field intensity over time as a function of the sun’s latitude. The two colors represent north and south polarity magnetism.

Unlike the Earth, where magnetic north has conveniently stayed in the Northern Hemisphere for the last 780,000 years, the sun’s magnetic field changes polarity every 11 years.