Climate Progress

Post image for Social Cost of Carbon: Interagency Group Predictably Predicts Climate Change Worse Than Predicted

Hold the presses! A U.S. Government interagency working group has just released its updated Technical Support Document (TSD) on the social cost of carbon (SCC).

This is joyous news in some circles. “The ‘Social Cost of Carbon’ Is Almost Double What the Government Previously Thought,” Climate Progress enthuses. Why are they pleased? Because the higher the SCC, the stronger the (apparent) case for suppressing the production and export of hydrocarbon energy in general, and for blocking the Keystone XL pipeline in particular.

SCC is an estimate of how much damage an incremental ton of carbon dioxide (CO2) emissions does to humanity and the biosphere. SCC estimates are driven by assumptions about such issues as climate sensitivity (how much warming results from a given increase in CO2 concentrations), climate impacts (how warming will affect weather patterns and sea-level rise), economic impacts (how changes in global temperature, weather, and sea-level rise will affect agriculture and other climate-sensitive activities), and technological change (how adaptive capabilities will develop as climate changes).

Modelers feed the assumptions into computer programs called “integrated assessment models” (IAMs). By tweaking those values, the modeler can get pretty much any result he desires. Outcomes also vary based on the discount rate selected, i.e., how much people are assumed to value income in the future compared to income in the present.

Using three IAMs, three discount rates (2.5,% 3,% and 5%), and a fourth value representing low-probability catastrophic impacts, the interagency group calculates four SCC estimates for the year 2020. In the working group’s 2010 TSD, the SCC estimates were $7, $26, $42, and $81 (2007$). In the updated TSD, the corresponding estimates are $12, $38, $58, and $129 (2007$). Excuse me, but even for the high-impact projections, the updated estimate ($129) is 59% higher than the 2010 estimate ($81), which is more than a tad shy of “almost double.”

Let’s cut to the chase. Those who say the SCC is bigger than the government previously thought merely recycle the old saw that climate change is ”worse than scientists previously thought.” They are mistaken. The climate change outlook is better than we have long been told.

One reason the updated estimates are higher is that the IAMs contain an “explicit representation” of sea-level rise “dynamics.” Are the modelers keeping up with the scientific literature? Consider two recent studies

  • King et al. (2012): The rate of Antarctic ice loss is not accelerating and translates to less than one inch of sea-level rise per century.
  • Faezeh et al. (2013): Greenland’s four main outlet glaciers are projected to contribute 19 to 30 millimeters (0.7 to 1.1 inches) to sea level rise by 2200 under a mid-range warming scenario (2.8°C by 2100) and 29 to 49 millimeters (1.1 to 1.9 inches) under a high-end warming scenario (4.5°C by 2100).

If 21st century sea-level rise is more likely to be measured in inches rather than feet or meters, shouldn’t SCC estimates decline?

And what about the 15-year period of no-net warming, which the climate science establishment did not predict and still struggles to explain? The warming pause is hard to square with the mantra of “worse than we thought.” It is evidence that the SCC is lower than they thought.

Let’s look at the disconnect between what they predicted and what happened.  The graph below comes from NASA scientist Roy Spencer[click to continue…]

Post image for Hurricane Sandy and Global Warming

Both the blogosphere and the mainstream media have been abuzz with commentary blaming global warming for Hurricane Sandy and the associated deaths and devastation. Bloomberg BusinessWeek epitomizes this brand of journalism. Its magazine cover proclaims the culpability of global warming as an obvious fact:

Part of the thinking here is simply that certain aspects of the storm (lowest barometric pressure for a winter cyclone in the Northeast) and its consequences (worst flooding of the New York City subway system) are “unprecedented,” so what more proof do we need that our fuelish ways have dangerously loaded the climate dice to produce ever more terrible extremes?

After all, argues Climate Progress blogger Brad Johnston, quoting hockey stick inventor Michael Mann, “climate change is present in every single meteorological event.” Here’s Mann’s explanation:

The fact remains that there is 4 percent more water vapor – and associated additional moist energy – available both to power individual storms and to produce intense rainfall from them. Climate change is present in every single meteorological event, in that these events are occurring within a baseline atmospheric environment that has shifted in favor of more intense weather events.

Well sure, climate is average weather over a period of time, so as climate changes, so does the weather. But that tautology tells us nothing about how much — or even how — global warming influences any particular event. Moreover, if “climate change is present in every single meteorological event,” then it is also present in ”good” weather (however defined) as well as “bad.”

Anthony Watts makes this criticism on his indispensable blog, noting that as carbon dioxide (CO2) concentrations have risen, the frequency of hurricanes making landfall in the U.S. has declined.

The US Has Had 285 Hurricane Strikes Since 1850: ‘The U.S. has always been vulnerable to hurricanes. 86% of U.S. hurricane strikes occurred with CO2 below [NASA scientist James] Hansen’s safe level of 350 PPM.’

If there’s anything in this data at all, it looks like CO2 is preventing more US landfalling hurricanes.

Data Source: NOAA; Figure Source: Steve Goddard [click to continue…]

Post image for Big Green Spent More, But Still Lost

Professor Matthew Nisbet of American University published a report last week that concludes, among much else, that environmental pressure groups spent a lot more money trying to pass cap-and-trade legislation than opponents spent trying to defeat it.  The report, “Climate Shift: Clear Vision for the Next Decade of Public Debate,” is part of the Climate Shift Project of American University’s School of Communications.

As someone who has been engaged in the global warming debate for over a decade, the conclusion that the cap-and-traders had more money than their opponents is not at all surprising.  In fact, it is obvious and recognized by everyone who has been paying attention.

But rabid attack dog Joe Romm of the hilariously-misnamed Center for American Progress, who got hold of a copy of the report before it was published, naturally attacked it viciously.  That’s because Nisbet’s analysis destroys the environmental movement’s carefully-cultivated mythology that they are a bunch of little citizen groups up against mammoth industry special interests led by Big Oil and King Coal.

[click to continue…]