Changing Planet

Presidential Candidates, Studies Dissect Climate Change

As campaigning for the November presidential election moves forward, President Barack Obama and his Republican challenger Mitt Romney spelled out their interpretations on one issue in a bit more detail than usual. To Science Debate, Obama identifies climate change as one of the most pressing concerns of the era and lists the steps he has taken during his term to mitigate the effects climate change. Mitt Romney, meanwhile, agrees that “human activity contributes to that warming, and that policymakers should therefore consider the risk of negative consequences.” But Romney offers a caveat: “However, there remains a lack of scientific consensus on the issue — on the extent of the warming, the extent of the human contribution, and the severity of the risk.” Neither Romney nor Obama suggest specific policies (subscription) to slow or guard against the effects of climate change.

More than 20,000 high-temperature records have been broken so far this year in the United States. A new study indicates that the number of species grew when global temperatures increased during periods in the geologic past. The timescales involved, roughly 500 million years, may cancel out any benefits from the rising temperatures.

Weather events linked to climate change could affect agricultural production significantly and cause dramatic food-price spikes within two decades. In their report “Extreme Weather, Extreme Price,” Oxfam researchers suggest extreme weather events such as the droughts and floods have been previously underestimated. More frequent extreme weather events will pose a more serious threat to the world’s poor, leading to millions of deaths from malnutrition among the world’s poorest if governments do not act on climate change. Another study on climate change and the food supply looks at whether it would be possible to increase global yields while reducing the use of agricultural inputs like water and fertilizers. They found that overall output of 17 of the world’s crops could be increased by 45 to 70 percent by closing the “yield gap”—that is, by reducing the tendency of farmers in many regions to produce less than their potential.

Arctic Sea Ice Melt Hits New Low

Arctic Sea ice hit a new record low of 3.6 million square kilometers—down from 4.2 million square kilometers Aug. 24. That leaves 25 percent of the original ice sheet intact, which means more summer sunlight is absorbed by a warmer Arctic Ocean. The melt, the BBC reported, is like adding 20 years of carbon dioxide emissions to the atmosphere. A Washington Post editorial argues that the extent of the recent losses “should shock Congress and the president into more aggressive action.”

A large reservoir of close to 4 billion tons of methane may lie beneath the Antarctic ice sheet. Release of the methane—a greenhouse gas 25 times more potent than carbon dioxide—has the potential to accelerate global warming. “There’s a potentially large pool of methane hydrate in part of the Earth where we haven’t previously considered it,” Jemma Wadham, professor of Glaciology at the U.K.’s University of Bristol and lead author the study in the journal Nature. “Depending on where that hydrate is, and how much there is, if the ice thins in those regions, some of that hydrate could come out with a possible feedback on climate.”

Oil and gas reserves in the Arctic may not be as significant as many think, because extracting these reserves is cheaper elsewhere. Prices for these resources must remain high for it to be profitable to recover petroleum resources in the region, a new study said.

Three-Quarters of Americans Favor New Fuel Economy Standards

As one of the key architects of a new U.S. Environmental Protection Agency rule doubling fuel economy by 2025 retires, a poll from the Consumer Federation of America found that 74 percent of Americans support the new standards. Most said higher fuel economy was important in their next vehicle purchase. The New York Times reported because California can set its own vehicle emissions standards, it has special place at the table in the negotiations over fuel economy standards. Some say the rule could give a significant boost to sales of electric vehicles, whose performance is measured in “miles per gallon equivalent” in order to account for electrical power in terms of fuel economy.

Meanwhile, India has approved a $4.1 billion plan to increase the number of hybrid and electric vehicles in the country. The goal: 6 million vehicles by 2020.

The Climate Post offers a rundown of the week in climate and energy news. It is produced each Thursday by Duke University’s Nicholas Institute for Environmental Policy Solutions.

Tim Profeta is the founding director of the Nicholas Institute for Environmental Policy Solutions. The Nicholas Institute is part of Duke University and focuses on improving environmental policy making worldwide through objective, fact-based research in the areas of climate change, the economics of limiting carbon pollution, oceans governance and coastal management, emerging environmental markets and freshwater concerns at home and abroad. In his role at the Nicholas Institute, Profeta has continued to use his experience on Capitol Hill to engage in climate change debates. His research has focused, specifically, on market-based approaches to environmental regulations—particularly energy and climate change policy. Other projects engage his expertise in environmental law and air pollution regulation under the Clean Air Act.
  • Dan Pangburn

    Ice can melt because the surrounding water is warmer than it was when the water froze. The planet has warmed a lot since the last glaciation and has been warming more or less regularly since the depths of the LIA until about 2001. The assertion that it is warmer at the end of a warming period is not very profound. The observation that arctic ice is melting is evidence that warmer water got to the arctic ocean but does not mean that the planet is still warming.

    Paraphrasing Richard Feynman: Regardless of how many experts believe it or how many organizations concur, if it doesn’t agree with observation, it’s wrong.

    The IPCC and many others perceive that increased atmospheric carbon dioxide was the primary cause of global warming. Measurements demonstrate that they are wrong.

    The average global temperature trend has been flat since 2001. No amount of spin can rationalize that the temperature increase to 2001 was caused by CO2 increase but that 25.2% additional CO2 increase had no effect on the average global temperature trend after 2001.

    Without human caused global warming there can be no human caused climate change.

    Average GLOBAL temperature anomalies are reported on the web by NOAA, GISS, Hadley, RSS and UAH. The first three all draw from the same data base of surface measurement data. The last two draw from the data base of satellite measurements. Each agency processes the data slightly differently from the others. Each believes that their way is most accurate. To avoid bias, I average all five. The averages are listed here.

    2001 0.3473
    2002 0.4278
    2003 0.4245
    2004 0.3641
    2005 0.4663
    2006 0.3930
    2007 0.4030
    2008 0.2598
    2009 0.4022
    2010 0.5298
    2011 0.3316

    A straight line (trend line) fit to this data has no slope. That means that, for over a decade, average global temperature has not changed. If the average thru July in 2012 (0.3431) is included, the slope is down.

    See other mistakes exposed by me at the Climate Realists web site.

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