Hurricane Sandy

By Evan

Open Climate Letter” – goes the headline. A pretty strange, and clearly not proofread, headline from the usual professional standards at the National Post. This is an open letter to the UN Secretary General from over 100 climate scientists (not all are actually climate scientists or geologists), saying that action of global warming is unnecessary. Surely, the Post has published this as it is sure to get a lot of readers. But let’s deconstruct this for a moment.

The letter starts with some quotes from Ban-Ki Moon and Al Gore on why it is necessary to have immediate action on man-made climate change, and that it will cost more to correct the problems if people wait. Recent events such as Hurricane Sandy are evidence of these problems. The letter begins:

We the undersigned, qualified in climate-related matters, wish to state that current scientific knowledge does not substantiate your assertions.

There we go, they suggest that climate science is not settled. Fair enough, there are limitations on what we know about climate. For instance, the role of water vapour and clouds on global climate is poorly understood.

The U.K. Met Office recently released data showing that there has been no statistically significant global warming for almost 16 years. During this period, according to the U.S. National Oceanic and Atmospheric Administration (NOAA), carbon dioxide (CO2) concentrations rose by nearly 9% to now constitute 0.039% of the atmosphere. Global warming that has not occurred cannot have caused the extreme weather of the past few years. Whether, when and how atmospheric warming will resume is unknown. The science is unclear. Some scientists point out that near-term natural cooling, linked to variations in solar output, is also a distinct possibility.

They don’t link to the MET Office Report, but on their website, they have a chart of their model of global temperatures for the past 160 years. The opening statement is a pretty clear example of cherry picking data, because the trend over the past 100 years is one of increased temperature. If you look at the data over the long term (that’s climate), you can say with high levels of confidence that the past 16 years have been statistically warmer than any time in the past 100 years. So although it may be correct that there is no observed statistical increase during the past 16 years, the data are highly variable, and the error is large. Simply put, 16 years is not long enough to determine a trend.

The statement: “carbon dioxide (CO2) concentrations rose by nearly 9% to now constitute 0.039% of the atmosphere” is a confusing one, and doesn’t really fit in with their argument. They acknowledge that CO2 levels have increased. I imagine the purpose of putting this number in the letter is to show that the level of CO2 in the atmosphere is small, as if to lead the reader on to think that the level is insignificant.

They then say that global warming that has not occurred cannot cause extreme weather changes. Except that ignores the fact that global temperature is an average – there are places that have warmed, while other areas have cooled. There is pretty clear evidence that the Arctic is experiencing unprecedented warming during the past 15 years, leading to low sea ice extent. Meanwhile, people throughout Australia can attest to nightime temperatures being below normal during the winter of 2012. The fact that global temperatures may have leveled out for 15 years may very well be masked by increased variability in weather patterns.

They then go on to talk about solar variability. 2008-2009 was the deepest solar minimum in over 100 years. 2008 was the eighth warmest year on record, while 2009 was tied for the second hottest. Any correlation between solar variability and climate change is pretty weak, and the only long term proxy we have is the sunspot record. Certainly, the recent sunspot minimum has had little effect on lowering global temperatures, at least in the short term.

One thing they mention is that it is unknown if global temperatures will begin to rise. Predicting the future is always risky business – just ask an economist. However, most climate models are based on physics, and tested on past climate records, so if they say increasing greenhouse gas emissions will cause temperatures to rise, I’d be willing to give them the benefit of the doubt.

The “even larger climate shocks” you have mentioned would be worse if the world cooled than if it warmed. Climate changes naturally all the time, sometimes dramatically. The hypothesis that our emissions of CO2 have caused, or will cause, dangerous warming is not supported by the evidence.

This is kind of a silly statement. Large increases of CO2 have been implicated in rapid climate change in the geological record. The Paleocene-Eocene Thermal Maximum, a rapid change in climate that caused global temperatures to increase by 5-8 degrees, caused extreme shocks to the Earth. It is thought that this event was caused by a rapid release of CO2 and other greenhouse gases in the atmosphere. Make no bones about it, the current release of CO2 in the atmosphere has caused levels to increase higher than any time in the past 400,000 years, at least. The climate system may be slow to respond to forcing mechanisms, so it is possible that we have not observed the worst effects.

The incidence and severity of extreme weather has not increased. There is little evidence that dangerous weather-related events will occur more often in the future. The U.N.’s own Intergovernmental Panel on Climate Change says in its Special Report on Extreme Weather (2012) that there is “an absence of an attributable climate change signal” in trends in extreme weather losses to date. The funds currently dedicated to trying to stop extreme weather should therefore be diverted to strengthening our infrastructure so as to be able to withstand these inevitable, natural events, and to helping communities rebuild after natural catastrophes such as tropical storm Sandy.

It is true that the frequency of extreme weather events, such as hurricanes, has not increased with statistical certainty. Is this the result of lack of observations, or because there has been no actual increase in the frequency of events? Prior to the advent of global satellite observations in the 1970s, the reporting of extreme weather events was limited to ground based observations, which is heavily biased to the continents, and first world nations. Even so, it is improper to attribute a years worth of hurricanes to climate change, let alone a single storm.

Still, their second statement is confusing, and doesn’t really serve as a reason to discount the first. Whether or not climate change has caused an increase in extreme weather events, you cannot disagree with the fact that major storms that cause widespread damage happen. What the heck does “funds currently dedicated to trying to stop extreme weather” even mean? My home province of Manitoba recently expanded the diversion floodway around the city of Winnipeg to prepare for a one in 700 year flood event. When the floodway was originally constructed, it was derisively called “Duff’s Ditch” after the premier, because it was seen by people as being a waste of money. It has saved the city from several floods, including the “Flood of the Century“. There is nothing wrong with planning for extreme weather events, including those that statistically not expected to happen in our lifetime. I just don’t know where the authors of this letter are going with this statement.

There is no sound reason for the costly, restrictive public policy decisions proposed at the U.N. climate conference in Qatar. Rigorous analysis of unbiased observational data does not support the projections of future global warming predicted by computer models now proven to exaggerate warming and its effects.

I think the saying that goes with this is “show me the money”. What is this “unbiased observational data” they are talking about? Which models have “proven to exaggerate warming and its effects”? Climatic data is freely available from most government agencies that produce it (such as the GISS database). Perhaps they mean that global coverage of data is biased, which is certainly true due to the distribution of land mass. Truly global temperature records only exist for perhaps the past 30 years, the era when satellite records became available. As such, the models of global climate are only as good as the assumptions to fill in the gaps. We should be instructed by the work of former climate skeptic Richard A. Muller, who spent two years trying to find problems with the global climate dataset, only to come to the conclusion that there was nothing wrong with it.

The NOAA “State of the Climate in 2008” report asserted that 15 years or more without any statistically-significant warming would indicate a discrepancy between observation and prediction. Sixteen years without warming have therefore now proven that the models are wrong by their creators’ own criterion.

As I mentioned earlier, this is a misleading statement. Cherry picking 16 years of data to draw up conclusions, especially given the errors involved, is improper. Is 15 years long enough to make any conclusions on climate? I am not sure, even if NOAA concluded that in 2008. Another study I found states that 17 years is a minimum time to make such conclusions, and even at 32 years, the signal to noise ratio is low. Any geophysicist will tell you, the longer the time series, the easier it is to make a conclusion, because a short time series always contains noise. As concluded in that article: “Minimal warming over a single decade does not disprove the existence of a slowly-evolving anthropogenic warming signal.”

Based upon these considerations, we ask that you desist from exploiting the misery of the families of those who lost their lives or properties in tropical storm Sandy by making unsupportable claims that human influences caused that storm. They did not. We also ask that you acknowledge that policy actions by the U.N., or by the signatory nations to the UNFCCC, that aim to reduce CO2 emissions are unlikely to exercise any significant influence on future climate. Climate policies therefore need to focus on preparation for, and adaptation to, all dangerous climatic events however caused.

Their concluding statement is confusing to me. They chide the UN for blaming Hurricane Sandy on anthropogenic climate change and that CO2 emissions are not influencing climate change. Then they say that policies should be in place to prepare for any extreme weather event. The point of this letter appears to be “climate change isn’t caused by anthropogenic emissions, but we should prepare for damage by major storms anyways”, which differs from most climate scientists who would say “climate change is caused by anthropogenic emissions, and we should prepare for damage by major storms that may happen more frequently”.

There is, of course, more to this problem than just global temperatures. Sea level has increased during the past 20 years (as Bianca wrote about earlier today), regardless of whether or not there has been a statistical increase in temperatures during this period. So even if the frequency of storms is not going up or becoming more severe, the impact these storms have on populated areas near sea level becomes worse. A great quote by Erik Ivins on this matter:

“When you have 11 millimetres of increased sea level, if you compute the amount of mass that’s capable of coming onshore during a storm surge, that’s a lot of mass,” Ivins told reporters. “And small changes in sea levels in certain places mean very big changes in the kind of protection of infrastructure that you need to have in place.”

If you look what happened in New Jersey and New York during Sandy, this was exactly the problem. Whatever the global climate change was during the past 20 years, sea level has increased, and this causes problems with infrastructure.

So really, I don’t see the point of this open letter, except to attract attention to themselves. Even those on the list who have legitimate problems with the state of climate science at present do themselves a great disservice by putting the likes of “Lord” Monckton on there.