The is an interesting news article by Quirin Schiermeier in Nature titled
This news summary contains both recognition (finally) of some the complications of assessing the role of humans in the climate system, but also continues to perpetuate misunderstandings of the latest science.
First, here are the main deficiencies in climate science (those parts of the text which I agree with) reprinted from the Nature article as excerpts;
1. “The sad truth of climate science is that the most crucial information is the least reliable. To plan for the future, people need to know how their local conditions will change, not how the average global temperature will climb. Yet researchers are still struggling to develop tools to accurately forecast climate changes for the twenty first century at the local and regional level.”
2. “….. Unfortunately, when it comes to precipitation, that is about all the models agree on. The different simulations used by the IPCC in its 2007 assessment offer wildly diverging pictures of snow and rainfall in the future ….. The situation is particularly bad for winter precipitation, generally the most important in replenishing water supplies. The IPCC simulations failed to provide any robust projection of how winter precipitation will change at the end of the current century for large parts of all continents.”
3. “Atmospheric aerosols — airborne liquid or solid particles — are a source of great uncertainty in climate science. Despite decades of intense research, scientists must still resort to using huge error bars when assessing how particles such as sulphates, black carbon, sea salt and dust affect temperature and rainfall.”
Each of these admissions move climate science further from the frequent claims that we hear that climate science issue is settled.
The article does, unfortunately perpetuate erroneous conclusions about the science. A number of these error are clearly stated in a section of the article “Enduring climate myths” on page 286 of the article. Several of the “myths” actually have substantive scientific evidence which refutes them, while others are not disputed by anyone.
Below I have commented on the “myths” ;
1. “Myth #1: “Climate models can’t provide useful information about the real world”.
I agree that climate models provide valuable insight into climate processes. I am aware of no one who concludes otherwise. Where there is disagreement is on their skill at regional and global averaged multi-decadal forecasts. Clearly, even the reporter concludes there is no regional skill on this time scale.
2. Myth #2: “Global warming stopped ten years ago.”
Actually global warming, as measured by lower tropospheric temperatures; e.g. see Figure 7 in the RSS MSU data) has been close to zero at least since 2002, and by upper ocean heat content (see) since 2003 (with other data such as Levitus showing since 2005 (see).
3. Myth #3: “Temperatures were higher in pre-industrial times”.
On this issue, I defer to experts who investigate proxy records. However, the kludging together of proxy data with the instrument record has always been a dubious excercise since they do not measure the same climate metric. I have discussed the divergence issue with respect to proxy and instrument temperature data based on the research of colleagues (see and see)
4. Myth #4:”Temperature records taken in the lower atmosphere indicate that the globe is not warming”.
The link to the UAH MSU data (see bottom figures in this post) and the RSS MSU data (see Figure 7) show that since 2002, warming has not occurred, on average, over this time period. Over the longer time period (since 1979) there has been warming. However, the failure by the reporter to recognize in the news article that this warming, at least for a few years, has stopped is obvious.
5. Myth #5: “A few degrees of warming are not a big deal.”
This is a vague statement. For example, an increase in nighttime minimum temperatures of several degrees might even be beneficial for some agriculture locations, while such an increase in the maximum temperatures could result in major problems. The reporter refers to a global average temperature warming, but without knowing how such an increase in temperatures were distributed regional and locally, and through the diurnal cycle, there is no way to know if it is a “big deal” or not.
6. Myth #6: “Measured increases in temperature reflect the growth of cities around weather stations rather than global warming.”
““Across the (United States) as a whole, approximately 50 percent of the warming that has occurred since 1950 is due to land use changes (usually in the form of clearing forest for crops or cities) rather than to the emission of greenhouse gases,” Stone said. “Most large U.S. cities … are warming at more than twice the rate of the planet as a whole — a rate that is mostly attributable to land use change.”
The article is a step forward from other news summaries of climate science. However, it still perpetuates significant misunderstandings and erroneous conclusions about our actual understanding of the climate system.