Tag: Global Science Report

The Progressive Increase of the Urban Heat Island’s Influence on Temperature Records

Global Science Report is a feature from the Center for the Study of Science, where we highlight one or two important new items in the scientific literature or the popular media. For broader and more technical perspectives, consult our monthly “Current Wisdom.”

Perhaps no other climatic variable receives more attention in the debate over CO2-induced global warming than temperature. Its forecast change over time in response to rising atmospheric CO2 concentrations is the typical measure by which climate models are compared. It is also the standard by which the climate model projections tend to be judged; right or wrong, the correctness of global warming theory is most often adjudicated by comparing model projections of temperature against real-world measurements. And in such comparisons, it is critical to have a proper baseline of good data; but that is easier acknowledged than accomplished, as multiple problems and potential inaccuracies have been identified in even the best of temperature datasets.

One particular issue in this regard is the urban heat island effect, a phenomenon by which urban structures artificially warm background air temperatures above what they normally would be in a non-urbanized environment. The urban influence on a given station’s temperature record can be quite profound. In large cities, for example, urban-induced heating can be as great as Tokyo’s 10°C, making it all the more difficult to detect and discern a CO2-induced global warming signal in the temperature record, especially since the putative warming of non-urbanized areas of the planet over the past century is believed to be less than 1°C.  Yet, because nearly all long-term temperature records have been obtained from sensors initially located in towns and cities that have experienced significant growth over the past century, it is extremely important that urbanization-induced warming – which can be a full order of magnitude greater than the background trend being sought – be removed from the original temperature records when attempting to accurately assess the true warming (or cooling!) of the natural non-urban environment. A new study by Founda et al. (2015) suggests this may not be so simple or straightforward a task.

Fatal Flaw in the USGCRP Climate and Health Assessment

Global Science Report is a feature from the Center for the Study of Science, where we highlight one or two important new items in the scientific literature or the popular media. For broader and more technical perspectives, consult our monthly “Current Wisdom.”

 

Yesterday, we posted some excerpts from the Background section of our submitted Comment on the draft report on climate and health from the U.S. Global Change Research Program (USGCRP). In that section, we argued that the USGCRP was overlooking (ignoring?) a vital factor that shapes the influence of climate change on the health and well-being of Americans—that is, that the adaptive process is actually spurred by climate change itself. Without recognition of this fact, projections are often alarmist and pessimistic.

Today, we wanted to highlight what we found to be the fatal flaw in the entire USGCRP report—that the USGCRP fails to describe the net impact of climate change on public health, instead, presenting only a narrow and selective look at what they determine to be negative impacts (and even those examples tend to be miscast).

Here’s what we had to say about this:

A Clear Case of Selective Data Usage from the U.S National Climate Assessment

Global Science Report is a weekly feature from the Center for the Study of Science, where we highlight one or two important new items in the scientific literature or the popular media. For broader and more technical perspectives, consult our monthly “Current Wisdom.”

In the process of writing our upcoming book, The Lukewarmer’s Manifesto, we wandered into the funhouse of the 2014 National Climate Assessment (NCA).

Recall that the NCA is a product of the federal government’s U.S. Global Change Research Program, whose motto isThirteen Agencies, One Mission: Empower the Nation with Global Change Science.”

In their case, “empower” is synonymous with “indoctrinate.”

Here is a good example:

The section on hurricanes in Chapter 2 (“Our Changing Climate”) caught our eye. The NCA has a sidebar on the history of the hurricane “power dissipation index” (PDI), a well-known cubic function of the wind velocity. The NCAs graphs  begin in 1970 and end in 2009 (a full four years before the NCA was released). They include a trend line through the PDI data beginning in 1980 that’s going up for whatever reason and that is apparently convenient for drawing an association with human-caused global warming. But had the NCA authors consulted a longer record, say, from 1920 to 2013 (the last year data was available for the 2014 NCA) they could have readily ruled out any role of global warming.

 

Figure 1. From page 42 of the hardcopy of the 2014 National Assessment Report form the USGCRP (available here).

California Drought: The Rest of the Story

Global Science Report is a weekly feature from the Center for the Study of Science, where we highlight one or two important new items in the scientific literature or the popular media. For broader and more technical perspectives, consult our monthly “Current Wisdom.”

When the national media covers a weather story these days, it almost certainly will find some angle in which to insert/assert an element of human-caused climate change, and that element will always be characterized such as to have made the situation worse. It would take a lot of thinking on our part to try to recollect a major weather-related story in which the global warming was suggested to have ameliorated the impact—this despite a scientific literature that is complex and nebulous as to the direction of most impacts, and even less certain regarding the current detectability of such impacts.

Take for example the coverage of the current drought in California. As the drought drags on with spring snowpack in the Sierra Nevadas at record low levels—a finding which has prompted California Gov. Brown to enact statewide water restrictions—the press is eager to finger our greenhouse gas-spewing modern economy as the prime culprit. The problem is most scientific research suggests that the lack of precipitation in California has its roots in natural variability (for example, this recent paper by Thomas Delworth and colleagues which finds a common cause to drought in the western U.S. and the hiatus in global warming).

Thus, for the time being at least, bedeviled by actual science, most in the press have resisted placing much of the blame on the lack of precipitation at the feet of anthropogenic global warming.

But, there are actually two components which contribute to drought: 1) lack of precipitation, and 2) high temperatures.

Stymied on the first, many in the media have turned to the second. 

Score a Victory for Cruz over Brown in Most Recent Climate Change Scuffle

Global Science Report is a feature from the Center for the Study of Science, where we highlight one or two important new items in the scientific literature or the popular media. For broader and more technical perspectives, consult our monthly “Current Wisdom.”

On Sunday, in anticipation of Sen. Ted Cruz’s (R-TX) announcement that he intends to run for president, California governor Jerry Brown (D), declared to NBC’s Meet the Press Cruz was “absolutely unfit to be running for office.” Why? Because of Cruz’s stance on climate change—some of which Cruz laid out on late night TV last week.

But comparing Cruz’s comments on Late Night with Seth Meyers and Brown’s remarks on Meet the Press, it is pretty clear that it is Gov. Brown who needs to spend more time familiarizing himself with the scientific literature on climate change and especially its associations with extreme weather events.

Apparently Gov. Brown is convinced that climate change, or rather the apparently scarier-sounding “climate disruption” Brown prefers, is behind the ongoing drought in California, not to mention the East Coast’s cold and snowy winter.

Cruz, on the other hand, told a more restrained story—that data doesn’t support many alarmist claims and that satellites show no warming during the past 17 years while climate models expected warming—one which comports better with the science that he portrayed.

While there is certainly more to the story than Cruz went into in his brief appearance with Seth Meyers, he is right, that according to satellite observations of the earth’s lower atmosphere as compiled by researchers at Remote Sensing Systems, there has been no overall temperature increase during the past 17 years.

Evidenced-based Sea Level Rise Projections Remain Low

Global Science Report is a feature from the Center for the Study of Science, where we highlight one or two important new items in the scientific literature or the popular media. For broader and more technical perspectives, consult our monthly “Current Wisdom.”

When it comes right down to it, the biggest potential threat from a warming climate is a large and rapid sea level rise. Everything else that a changing climate may bring we’ve seen before (or at least the likes of it), recovered from, and are better off for it (i.e., gained experience, learned lessons, developed new technologies, etc.). In fact, the more often extreme weather occurs, the more adaptive is our response (see for example, decreasing mortality in heat waves). So in that sense, climate change may hasten our adaptive response and reduce our overall vulnerability to it.

A large and rapid sea level rise is a bit of a different story—although perhaps not entirely so.

While we do have a large amount of infrastructure (e.g., big cities) in low-lying coastal regions, it is completely wrong to show them underwater in the future—a typical device used by climate activists. What will happen is that we will act to protect the most valued portions of that infrastructure, as shown in a recent report from leading experts (including from the U.S. Environmental Protection Agency) on sea level rise and response.

But, while targeted action will save our big cities, there is still a lot of real estate that will be lost if sea level rises a large amount in a short amount of time (say, by more than a meter [a little more than 3 feet] by the end of the 21st century).

We therefore keep a vigilant eye on sea level rise research. And what we’ve concluded is that sea level rise by the year 2100 is very likely to be quite modest, say about 15 inches—an amount that should allay concerns of a catastrophe. We’ve detailed literature in support of our conclusions here, there, and elsewhere.

This week, a new paper has come to our attention that further supports our synthesis.

Mega Drought in the Pacific Southwest?

Global Science Report is a feature from the Center for the Study of Science, where we highlight one or two important new items in the scientific literature or the popular media. For broader and more technical perspectives, consult our monthly “Current Wisdom.”


On Page 3 of Friday’s Washington Post is (yet another) lurid climate story, this time about mega-droughts of several decades that are going to pop up in the Pacific Southwest around 35 years from now. The findings are based upon the UN’s climate model suite that, according to our presentation to the American Geophysical Union, is in the process of failing, because it just isn’t warming at the rate they project. Here, for example, is a graphic from John Christy and Dick McNider of the University of Alabama-Huntsville, showing the growing disparity.

The work cited in the Post ignores this teensy-weensy little problem and, instead drives the models with the UN’s biggest scenario for future carbon dioxide emissions, something that natural gas, which emits much less carbon dioxide than coal when used for electrical generation, is in the process of burying.

But it gets worse.

Droughts in the Pacific Southwest are usually broken by the big pacific climate oscillation known as  El Niño.  They occur every four to eight years or so. So, in order to have decades of drought, there has to be decades without El Niños.

The overdriven, overheated climate models used in this study cannot simulate them with any degree of realism.

That’s why, in the Post article, study co-author Toby Ault

had a word of caution.  Weather conditions can vary, climate impacts can be mitigated, and the warnings of the study might not come to pass. A single El Niño weather pattern in the West could interrupt periods of prolonged drought.

At least younger climate scientists like assistant professor Ault are getting wiser. The fates willing, he’s going to live another 35 years, and we hope much longer. And when those pesky El Niños (along with many other potential co-conspirators) destroy the forecast of gloom and doom, he’ll be able to say that he warned that could happen, because the models his team used didn’t have a good handle on them.

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