Guess what! Since 2016, there have been nearly 90 studies showing what common sense dictates, that there is nothing unusual, nothing unprecedented or remarkable about today’s climate when seen in the context of historical records. One study observed, “1970-2000 was colder than the last stages of the Little Ice Age.” Let that sink in, that the last third of the 20th century matched the temperature coming out of the Little Ice Age some two centuries previous.
During the latter stages of the medieval warming period, graps harvesting occurred between 100 to 500 Kilometers North of where grapes are being harvested in Great Britain today. This shows that today’s temperatures may not be unusual. There are numerous studies showing that grapes were harvested north of where they are presently harvested. Some researchers conclude between 900 to 1300, temperatures were as high, if not higher, than today despite CO2 being lower than today.
The key element is that now we will have a real debate on climate change. It will review, not just human contributions, but natural events that have affected climates for millions of years.
MIT Scholar Richard Lindzen issued a letter signed by 300 fellow scientists to Donald Trump saying it is time for United States to leave the UN intergovernmental Panel on Climate Change (IPCC). He summarizes his case:
“We note that:
- The UN’s Intergovernmental Panel on Climate Change (IPCC) no longer claims a greater likelihood of significant as opposed to negligible future warming.
- It has long been acknowledged by the IPCC that climate change prior to the 1960’s could not have been due to anthropogenic greenhouse gases. Yet, pre-1960 instrumentally observed temperatures show many warming episodes, similar to the one since 1960, for example, from 1915 to 1950, and from 1850 to 1890. None of these could have been caused by an increase in atmospheric CO2.
- Model projections of warming during recent decades have greatly exceeded what has been observed.
- The modelling community has openly acknowledged that the ability of existing models to simulate past climates is due to numerous arbitrary tuning adjustments.
- Observations show no statistically valid trends in flooding or drought, and no meaningful acceleration whatsoever of pre-existing long term sea level rise (about 6 inches per century) worldwide.
- Current carbon dioxide levels, around 400 parts per million are still very small compared to the averages over geological history, when thousands of parts per million prevailed, and when life flourished on land and in the oceans.
“Calls to limit carbon dioxide emissions are even less persuasive today than 25 years ago. Future research should focus on dispassionate, high-quality climate science, not on efforts to prop up an increasingly frayed narrative of “carbon pollution.” Until scientific research is unfettered from the constraints of the policy-driven UNFCCC, the research community will fail in its obligation to the public that pays the bills.”
This letter is a summary of what the debate is all about. What we don’t know about climate change exceeds what we think we know and we are being asked to base economic policy on questionable science.