Summer heat and storms bring out the worst in climate warmist. “Hottest summer on record..” (no it isn’t) and we can “expect more unusual storms and damage due to climate change” (no we cant). Weather events have their own historiographies and causes, but don’t confuse weather with climate or climate change with one off events. In fact, global temperatures so far in 2012 have been below the fifteen year average.
But it is a helpful prompt to look at new information about the state of climate science.
First, an important analysis of the veracity of computer models of climate will shortly appear from Ross McKitrick (preview here). Looking at all of the “in use” models he finds that none are especially good at predicting regional climate (when compared to actual data) and that, taken together, the models are based on a limited understanding of climate and a particular model of climate change – one that makes assumptions about the role of CO2. Given that so much of what we see is based on these “virtual science” analysis as opposed to actual data, then we need to treat all of these models with a great deal of caution.
This also applies to polar bear population analysis. The models show declining populations in four groups of polar bears, whereas observation and tagging data suggests that polar bears are actually doing rather well – according to the International Union for Conservation of Nature estimates, polar bear numbers are at least twice as high as in the 1960s (here).
Second, new evidence appears that we have been underestimating how warm it was in the past. The team of scientists (see here), led by Professor-Doktor Jan Esper of the Johannes Gutenberg-Universität Mainz, suggest that the available tree ring data shows that it was much warmer in the Roman and medieval period than it is today – a time when less CO2 was in the atmosphere than is the case today. Indeed, their analysis of these data suggest that there has been a gradual cooling over time.
A related study shows that the coral reefs around Australia were wiped out some 4,000 years ago when it was much warmer than it is now by about 2C (here). The culprit in this past case was not C02 but ENSO - the climate cycle responsible for the weather conditions every few years known as El Niño and La Niña events. The timing of the shutdown in reef growth corresponds to a period of wild swings in ENSO. Since corals are resilient, they have regrown after a shutdown that lasted over 2,500 years.
Then we look at the north and south poles. Contrary to media hype, the vast majority of Antarctica has cooled over the past 50 years and ice coverage has grown to record levels since satellite monitoring began in the 1979, according to peer-reviewed studies and scientists who study the area. (LINK) In the Arctic things are different. NSDIC shows that the Arctic ice had expanded enough from its lows of 2007 to meet the average level that existed over the last three decades. Another source, the National Energy Research Scientific Computing Center, shows the Arctic ice to have exceeded the three-decade average. While this summer the melt is substantial – the largest in recent times – the recovery and resilience of the region has been demonstrated time and time again (see here). Newly discovered maps of the Arctic sea-ice extent in the earlier decades of the 20th century make clear that the sea-ice extent in the decades around 100 years ago was much less than it is today. In many years, there was virtually a northwest passage clear of ice along the Russian side.
Critics of the theory of CO2 causing substantive warming (and it is one theory of several) like to point to the suggestion that this is a cooling time. While the models suggest something different, observation suggests that there has been no significant global warming since 1998 (here). Indeed, there is a growing realization amongst the scientific community that the CO2 theory is flawed. What is emerging in its place is a focus on the role of the sun as a major determinant of climate. New research at the Danish Space Research Institute and Geneva-based CERN has been affirming this cosmic ray-Sun theory, and other prestigious scientific bodies were giving it credence, including the Royal Astronomical Society’s publication of an important new work that continues the ascendancy of this theory ( here).
So, don’t be alarmed by extreme weather events as “evidence of man made global warming”. Keep a critical, scientific mind which is open to evidence based analysis not policy based evidence finding.