6)
Extreme Events
“As a climatologist who has studied the Earth’s climate for nearly forty years, I have learned that carbon dioxide is not a climate control knob; it is merely a minor player in climate change. Water vapor is the most important greenhouse gas and it accounts for nearly 90% of the net warming of the planet due to the radiative impact of the Earth’s atmosphere.” David R. Legates (2019). “It is well known that strong to violent tornado activity in the US has decreased markedly since statistics began in the 1950s, which has also been a period of average warming. So, if anything, global warming causes FEWER tornado outbreaks...not more. In other words, more violent tornadoes would, if anything, be a sign of 'global cooling,' not 'global warming.” Roy Spencer As Pielke (2017) said in his address and testimony to the Committee on Science, Space and Technology of the U.S. House of Representatives “Scientific evidence in support of the conclusions I presented to this committee in 2013 is even stronger today. There is little scientific basis in support of claims that extreme weather events – specifically, hurricanes, floods, drought, tornadoes – and their economic damage have increased in recent decades due to the emission of greenhouse gases. In fact, since 2013 the world and the United States have had a remarkable stretch of good fortune with respect to extreme weather, as compared to the past”. He then added “The lack of evidence to support claims of increasing frequency or intensity of hurricanes, floods, drought or tornadoes on climate timescales is also supported by the most recent assessments of the IPCC and the broader peer reviewed literature on which the IPCC is based” (Pielke, 2017). In fact, browsing through (IPCC, 2012) and (IPCC, 2013) one can only concur with Pielke (2017) and be surprised of the harassment he reports having been victim of, for his honest stance and his unbiased report of the facts. “There is low confidence in any observed long-term (i.e., 40 years or more) increases in tropical cyclone activity (i.e., intensity, frequency, duration), after accounting for past changes in observing capabilities”. SREX, p.8, (IPCC, 2012) The better are the observations and the more accurate are the records, the less confidence IPCC have in an increase in tropical cyclone activity. “There is medium confidence that some regions of the world have experienced more intense and longer droughts, in particular in southern Europe and West Africa, but in some regions droughts have become less frequent, less intense, or shorter, for example, in central North America and northwestern Australia “ SREX, p.8, (IPCC, 2012) So, there is no global drought trend but only regional phenomenons, some more some less intense or frequent. “The uncertainties in the historical tropical cyclone records, the incomplete understanding of the physical mechanisms linking tropical cyclone metrics to climate change, and the degree of tropical cyclone variability provide only low confidence for the attribution of any detectable changes in tropical cyclone activity to anthropogenic influences. Attribution of single extreme events to anthropogenic climate change is challenging”. SREX, p.9, (IPCC, 2012) If it is challenging for IPCC and SREX authors to attribute any change in tropical cyclone activity to anthropogenic influences, one can hardly imagine who will succeed! “Projected changes in climate extremes under different emissions scenarios generally do not strongly diverge in the coming two to three decades, but these signals are relatively small compared to natural climate variability over this time frame. Even the sign of projected changes in some climate extremes over this time frame is uncertain”. SREX, p.11, (IPCC, 2012) The IPCC tells us that the natural variability is way bigger than the “signals” coming from their anthropogenic influence scenarios and that in the end that they do not even know the sign (!), i.e. which is whether these climate extremes will increase or decrease!
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