Millions are suffering and thousands have died from flooding in Pakistan and China. An extraordinary heat wave in Russia sparked fires that caused dreadful pollution and wiped out swathes of the wheat crop. Are these weather-related disasters caused by global warming?
In its most recent report, the UN’s Intergovernmental Panel on Climate Change asserts that as the world becomes warmer, “flood magnitude and frequency are likely to increase in most regions.” This seems plausible. A warmer world is also likely to be a wetter world, as more water evaporates from the oceans into the atmosphere. But, although rainstorms put out some of the fires, Russia has a drought.
The UN panel also claims that droughts are more likely in a warmer world - and that they have become more frequent since the 1970s, partly because of reduced precipitation. In fact, the number of droughts reached a low point between the mid-1970s and mid-1980s. Evidence shows that there has been no statistically significant increase in droughts since the 1950s. Given that global temperatures appear to have risen considerably since then, it seems a stretch to blame the Russian drought on global warming.
Underpinning both the floods in Pakistan and China and the drought in Russia is a change in the usual pattern of the jet stream. Each hemisphere has a “polar” jet (seven to 12 kilometers above sea level) and a “subtropical” jet (at 10 to 16 kilometers). In the northern hemisphere, the polar jet pushes cooler air south and induces rain in mid-latitudes, while the subtropical jet pushes warm air north. But in mid-June, a kink appeared at the intersection, causing warm air to remain further north and east than normal and causing more cold air and rain to fall over northern Pakistan and China.
To make matters far worse, this kink in the jet stream was kept in place by a phenomenon called a “blocking event.” This kept the Russian heat wave going for nearly two months and massively exacerbated the precipitation in Pakistan and China.
Such blocking events are rare, and there is no evidence of links with global warming. However, an explanation has been proposed by Professor Mike Lockwood, an astrophysicist at the University of Reading in Britain, who shows in a recent paper that blocking events in the winter are related primarily to solar activity. (Although he cautiously said in an e-mail to me that he “cannot say much (yet) about summer conditions as most of our work to date has been on wintertime, which shows relatively strong solar effects in the Eurasian region").
So the culprit is quite possibly the sun, not human emissions of greenhouse gases.
Comparison of the last four solar cycles, note how cycle 23 was long and our recovery out of it into cycle 24 very slow. This is more like the cycles in the early 1900s and especially the early 1800s.
As for remedies, the current disasters demand a major humanitarian response. Worst affected is Pakistan, where an estimated 6 million people face cholera and other waterborne diseases unless they urgently get potable water. Pakistan’s government responded slowly, making immediate national and international philanthropy even more important.
But what of the longer term? Floods, droughts and other weather disasters have plagued mankind for all of history. But deaths from such natural disasters have fallen by more than 90 percent in the past 100 years despite dramatic population growth. Why? Because higher wealth and better technology enable people better to cope. This is a silver lining to this summer’s natural disasters. See post here.
Julian Morris is a visiting professor at the University of Buckingham and executive director of International Policy Network, London, an independent economic think tank. Richard Lourie will return to this spot in September.
Poor Al Gore. As if an im- pending divorce and allegations of sexual misconduct from an Oregon masseuse weren’t bad enough (he has since been cleared of wrongdoing), the apparent collapse of “cap-and-trade” legislation in the U.S. Senate has driven the former vice president to despair.
As reported by Steve Milloy on his blog Green Hell, Mr. Gore recently admitted to supporters in a conference call, “[T]his [cap-and-trade] battle has not been successful and is pretty much over for this year.” Mr. Gore blamed everyone and their monkey for the failure of Congress to pass comprehensive climate legislation, including his former colleagues: “The U.S. Senate has failed us,” he lamented, “the federal government has failed us.”
The fortunes of Mr. Gore’s global-warming crusade certainly are in decline: A recent Rasmussen poll found that just 34 percent of respondents “feel human activity is the main contributor” to global warming and that the percentage of those who consider global warming a “serious issue” has “trended down slightly since last November.”
Mr. Gore himself is to blame for at least some of the public backlash against global-warming orthodoxy: Using bad science to justify bad policy will inevitably rub people the wrong way. And Mr. Gore has not helped his cause by consistently expressing outrageous falsehoods ("the debate is over") and shamelessly trying to shield his assertions from legitimate criticism by claiming “settled science.” All the while, he has enriched himself and pushed a left-wing economic agenda.
Take, for example, the infamous “hockey stick” graph, a version of which was featured prominently in Mr. Gore’s documentary “An Inconvenient Truth.” The graph appeared to show global temperatures relatively flat for a millennium and then suddenly spiking upward in the late 20th century - proof, according to Mr. Gore and his acolytes, of man-made global warming caused by industrial carbon emissions.
Temperature records for the past century are based on instrumental data: thermometers, satellites, etc. For prior centuries, however, scientists rely on proxy data; in the case of the original hockey-stick graph, researchers relied on tree rings. But as Roy Spencer, former senior scientist for climate studies at NASA’s Marshall Space Flight Center, writes in “The Great Global Warming Blunder,” “the most recent tree-ring data do not even show the warming that occurred in the second half of the 20th-century, but appear to indicate a cooling instead.” Because tree rings do not show the recent warming that we know occurred, it follows that tree rings are not an adequate proxy by which we can accurately gauge past temperatures.
The unreliability of tree-ring data has long been known. Nevertheless, the hockey-stick graph was embraced enthusiastically by Mr. Gore and the global-warming crowd, for it conveniently dispensed with two significant climate events: the Medieval Warm Period (10th to 13th centuries) and the Little Ice Age (14th to 19th centuries). The former saw temperatures in the North Atlantic warm enough that vikings could settle and flourish in a lush Greenland, the latter temperatures so low that people routinely ice-skated on a frozen River Thames. Both of these climate events, for which there are masses of historical evidence, began before the Industrial Revolution and therefore are unattributable to man-made carbon emissions.
That’s why the global-warming crowd was so desperate to hide them: If people realize that temperature fluctuations occur naturally and cyclically, they are less likely to embrace the draconian, job-killing energy taxes favored by Mr. Gore and his ilk as punishment for their own carbon sins.
The hockey stick conveniently hid this natural temperature variation - for a while. Fortunately, thanks largely to the tireless work of independent researchers Steve McIntyre and Ross McKitrick, the flaws in the statistical methodology used to create the various hockey-stick graphs have received widespread attention, and the once-iconic symbol of global warming has since been largely marginalized in the climate-change debate.
But not before it helped Al Gore to earn an Academy Award, a Nobel Peace Prize and an undeserved reputation as a scientific guru. As The Washington Post once noted of Mr. Gore’s academic credentials: “For all of Gore’s later fascination with science and technology, he often struggled academically in those subjects. The political champion of the natural world received [a] sophomore D in Natural Sciences 6 ... and then got a C-plus in Natural Sciences 118 his senior year.”
Imagine: We nearly let this former politician, who barely passed sophomore science at Harvard, persuade us to acquiesce to the monstrous statism of cap-and-trade, which would have resulted in higher energy and food prices and imposed yet another economic hardship on the poorest members of our society. All in the name of bad science.
Shame on him. And thank God he failed.
Matt Patterson is editor of Green Watch, a publication of the Capital Research Center.
The fossil record from oceans around New Zealand shows a sudden discharge of carbon dioxide (CO2) into the atmosphere at the end of the last ice age, raising the possibility that a similar process may occur as a result of global warming, researchers say.
“We know that carbon dioxide cycles between the oceans and the atmosphere and that rising global temperatures cause the release of carbon dioxide from the deep ocean into the air,” Auckland University researcher Phil Shane said in a statement.
“But we found that the release of carbon dioxide from the Southern Ocean at the end of the last ice age was much faster than anticipated - on a scale of hundreds rather than thousands of years.”
The research, published in the latest issue of Nature, was conducted by scientists from New Zealand, the United States, and Spain. They examined microfossils in ocean sediment cores from the Bay of Plenty and the Chatham Rise, and Shane determined the chemical “fingerprint” of volcanic ash layers within the cores, providing crucial information about the age of the sediments.
Dating of two sediment cores from near New Zealand to be between 13,000 and 19,000 years old helped not only determine when the large CO2 release occurred but also the ocean pathway by which it escaped.
In recent years, other researchers have suggested some of that CO2 flowed back into the northern hemisphere rather than being entirely released into the atmosphere of the southern hemisphere.
But the new data - taken from cores of ocean sediments 600 meters to 1200 metres below the sea - suggest this “de-gassing” was regional, not global. If the effect was not global, then the North Pacific may be more important than previously thought in the comings and goings of ice ages.
And the research also has important implications for understanding what controls where and how CO2 comes out of the ocean, and how fast.
Factors involved include not only chemistry and ocean circulation but also the extent to which tiny phytoplankton and other photosynthesising organisms use CO2, then die and take carbon to the ocean floor.
During the last ice age, the level of CO2 in the atmosphere was lower because much of it was trapped in the bottom of the oceans. The circulation of oxygen through the deep Southern Ocean slowed considerably, but as the ice began to melt, the CO2 began to leak back into the atmosphere, eventually escaping quickly as warming intensified, and so thoroughly, that there was little trace of it in the NZ samples.
Today, the CO2 level in the atmosphere has been rising in the past 200 years, pushing up the levels in the ocean.
“Human activities are pumping carbon dioxide into the atmosphere at an unprecedented rate and the build up of this important greenhouse gas is believed to contribute to global warming. It is also forcing much more carbon dioxide into the sea,” said Shane.
“If, as we have seen, the natural process of global warming at the end of the last glacial period caused the sudden release of extra carbon dioxide from the oceans into the air, there is reason to believe that a similar process might occur as a result of man-made global warming, further adding to the problem”.
As we have covered in previous essays, global warming alarmists insist that the southwestern United States is getting drier and will get substantially drier in the future due to the buildup of greenhouse gases. They bolster their claims by results from a relatively large number of articles in the professional scientific literature and countless comments in various UN IPCC reports. Throw in pictures of declining water levels at Lake Mead, some fountains in Las Vegas and golf courses in Phoenix, and just like magic, a scary scenario is produced.
As with virtually every other element of the climate change issue, the literature produces some surprises, and the drought in the Southwest claim runs up against some interesting realities. The latest article on this subject appears in a recent issue of the Journal of Geophysical Research and once again, the results are at odds with the popular perception of increased drought in the Southwest.
This recent work was produced by scientists with the U.S. Geological Survey and the University of Delaware and had to survive the peer-review process for this respected journal of the American Geophysical Union. The final two sentences reveal where this is going as McCabe et al. conclude “El Nino events have been more frequent, and this has resulted in increased precipitation in the southwestern United States, particularly during the cool season. The “increased precipitation is associated with a decrease in the number of dry days and a decrease in dry event length.” What? More rain and fewer dry periods? We knew right away this would be featured in World Climate Report.
The authors focused on the Southwest “because (1) it has the highest consumptive use of water as a percentage of renewable supply in the United States and (2) dry event conditions in this region during the early 21st century have increased awareness of its vulnerability to water shortages.” There is no doubt that a lot of people have chosen to live in the Southwest and there is no doubt the desert climate of the region is prone to drought. In many respects, and depending on how one defines drought, the area is permanently in a state of drought (Phoenix has 7” of rain a year, Las Vegas averages about half of that amount).
McCabe et al. gathered data from 22 Weather Bureau-Army-Navy (WBAN) stations in the region “for water years (October through September) 1951 through 2006”. They explain that “During this period, 22 sites have nearly complete (99% complete) daily precipitation data. WBAN stations were selected because of the completeness of data record and the relative consistency of observational procedures.” They conducted their analysis for water years (October through September), cool seasons (October through March), and warm seasons (April through September).
They report that “trends in the fraction of dry days for water years, cool seasons, and warm seasons indicate that most trends are negative [i.e. towards more wet days, -eds.]. For water years, 18 sites exhibit negative trends in the fraction of dry days, and eight of these trends are statistically significant at a 95% confidence level. In contrast, only four sites indicate positive trends in the fraction of dry days for water years, and none of these trends is statistically significant at p = 0.05. For the cool season, 19 sites exhibit negative trends (12 are statistically significant at p = 0.05), and only 3 sites indicate positive trends (none are statistically significant).”
In this desert environment, cool season rain is far more important that rain in the summer. Rain falling in the hot summer season quickly evaporates and plays a relatively small role in water storage in the region. Nonetheless, the authors note that “For the warm season, 14 sites exhibit negative trends (seven are statistically significant), and 8 sites exhibit positive trends (six are statistically significant).”
The plot below (Figure 1) nicely reveals what has happened in the region. The number of dry days dropped over the entire study period but increased since 2000 (if you haven’t heard, the Southwest just experienced an unusually wet winter in 2009-2010). The authors varied the starting and ending dates in this time series of dry days and concluded “Examination of the counts of statistically significant trends in dry event length indicates small numbers of sites with significant positive trends for any period”.
Figure 1. Five year moving time series of the mean fraction of days with daily precipitation below 2.54 mm for water years (October through September), cool seasons (October through March), and warm seasons (April through September) (from McCabe et al., 2010). Enlarged here.
McCabe et al. make a number of interesting comments that do not support the claims that the Southwest is drying; they state “Our results are consistent with analyses of trends in discharge for sites in the southwestern United States, an increased frequency in El Niño events, and positive trends in precipitation in the southwestern United States.” They elaborate noting “Since the mid-1970s, the frequency of El Niño events has been higher than the long-term average. Precipitation in the southwestern United States generally is greater during El Nino years than during normal and La Nina years. Increased precipitation in the southwestern United States associated with the higher frequency of El Nino events since the mid-1970s should result in decreased drought length”.
The McCabe et al. team concludes “Little evidence of long-term positive trends in dry event length in the southwestern United States is apparent in the analysis of daily WBAN precipitation data. During the mid-1990s to late 1990s, drought conditions began in the southwestern United States and persisted in the 21st century. This drought has resulted in positive trends in dry event length for some sites in the southwestern United States. However, most of the statistically significant trends in the number of dry days and dry event length are negative trends for water years and cool seasons.” Furthermore, they conclude “Since the mid-1970s, El Nino events have been more frequent, and this has resulted in increased precipitation in the southwestern United States, particularly during the cool season. The increased precipitation is associated with a decrease in the number of dry days and a decrease in dry event length.”
As with so many other articles we feature, had this group found general trends toward drier conditions, you would have heard about it already. They clearly did not, and their results are counter to the claims that the region should be trending to increased drought. That’s why you come to World Climate Report for a different perspective on what is really found in the scientific literature!
Reference:
McCabe, G. J., D. R. Legates, and H. F. Lins. 2010. Variability and trends in dry day frequency and dry event length in the southwestern United States, Journal of Geophysical Research, 115, D07108, doi:10.1029/2009JD012866.
My friend Tamino says that “the modern global warming era starts in 1975.”
He goes on : “It’s an estimate of the time at which the trend in global temperature took its modern value.”
As you can see in Phil Jones’ HadCRUT graph above, the 25 year period from about 1975 to 2000 did warm about half a degree C.
You can also see that the 30 year period from 1910 to 1940 similarly warmed about half a degree C. At that time, atmospheric CO2 averaged about 305 ppm, well below Dr. Hansen’s suggested “safe level” of 350 ppm. See the graph below for that period:
Here’s an annotated HadCRUT graph to help you see the relevant periods and the changes of temperature versus changes in global CO2 concentration during the same period:
The video below superimposes the 1975 warming (blue line) on the 1910 warming (black line.) Note the similarity in slope, duration and patterns. It would be difficult to explain the 1910 warming as being due to CO2, because CO2 was barely above pre-industrial levels and rose only 10 ppm during that period.
Given the similarity between the 1975 warming and the 1910 warming, it is irrational to blame the 1975 warming entirely on CO2. The practice of good science tells us to look for a hypothesis which can explain both similar warming periods.
If there is an influence of CO2 in the recent warming, it appears small. And the warming stopped ten years ago, as shown in the HadCRUT graph, despite rapid increases in CO2.
Or perhaps one might conclude that climate sensitivity has decreased as CO2 levels have risen. In 1910, with CO2 at 300 ppm, it only took ten additional ppm to raise temperatures by 0.5°C. By contrast, in 1975 it took about fifty ppm more to produce the same 0.5C warming by the year 2000.
There were also periods of time with rising CO2, and little or no rise in temperature. From 1940 to 1980, there was no net warming while CO2 rose by 30 ppm. Since 1998, there has been no warming - as CO2 levels have risen 30 ppm.
