Leading scientists, including climate change experts, complain about opinion piece akin to ‘dentists practising cardiology’

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The Wall Street Journal has received a dressing down from a large group of leading scientists for promoting retrograde and out-of-date views on climate change.

In an opinion piece run by the Journal on Wednesday, nearly 40 scientists, including acknowledged climate change experts, took on the paper for publishing an article disputing the evidence on global warming.

The offending article, No Need to Panic About Global Warming, which appeared last week, argued that climate change was a cunning ploy deployed by governments to raise taxes and by non-profit organisations to solicit donations to save the planet.

It was signed by 16 scientists who don’t subscribe to the conventional wisdom that climate change is happening and is largely man-made – but as Wednesday’s letter points out, many of those who signed don’t actually work in climate science.

“Do you consult your dentist on your heart condition? In science, as in any area, reputations are based on knowledge and expertise in a field, and on published, peer-reviewed work. If you need surgery, you want a highly experienced expert in the field who has done a large number of the proposed operations,” the article said.

The scientists went on: “On 27 January, the Wall Street Journal published an op-ed on climate change by the climate science equivalent of dentists practicing cardiology. While accomplished in their own fields, most of these authors have no expertise in climate science. The few authors who have such expertise are known to have extreme views that are out of step with nearly every other climate expert.

“This happens in nearly every field of science. For example, there is a retrovirus expert who does not accept that HIV causes Aids. And it is instructive to recall that a few scientists continued to state that smoking did not cause cancer, long after that was settled science.”

The graphic is from here.

Let’s consider for a moment which groups have expressed their concern about climate change. Above, I link a joint statement from the national science academies of the G8, Brazil, China, and India.

Let’s also look at what the planet is telling us. Arctic sea ice continues to decline, global temperatures continue to rise, the atmospheric concentration of CO2 continues to increase, and the world continues to burn fossil fuels at a frightening pace.

I don’t think the letter you cite is any cause for diminished concern about climate change.

http://www.dailymail.co.uk/sciencetech/article-2093264/ Forget-global-warming–Cycle-25-need-worry-NASA-scientis ts-right-Thames-freezing-again.html

Cheers!

• The peak warming is linearly proportional to the cumulative carbon emitted
• It doesn’t matter much how rapidly the carbon is emitted
• The warming you get when you stop emitting carbon is what you are stuck with for the next thousand years
• The climate recovers only slightly over the next ten thousand years
• At the mid-range of IPCC climate sensitivity, a trillion tonnes cumulative carbon gives you about 2C global mean warming above the pre-industrial temperature.

FOR those who question whether global warming is really happening, it is necessary to believe that the instrumental temperature record is wrong. That is a bit easier than you might think.

There are three compilations of mean global temperatures, each one based on readings from thousands of thermometers, kept in weather stations and aboard ships, going back over 150 years. Two are American, provided by NASA and the National Oceanic and Atmospheric Administration (NOAA), one is a collaboration between Britain’s Met Office and the University of East Anglia’s Climate Research Unit (known as Hadley CRU). And all suggest a similar pattern of warming: amounting to about 0.9°C over land in the past half century.

To most scientists, that is consistent with the manifold other indicators of warming—rising sea-levels, melting glaciers, warmer ocean depths and so forth—and convincing. Yet the consistency among the three compilations masks large uncertainties in the raw data on which they are based. Hence the doubts, husbanded by many eager sceptics, about their accuracy. A new study, however, provides further evidence that the numbers are probably about right.

The survey, is known as HIPPO, comprised several pole-to-pole research flights that successfully collected atmospheric gases in three years and generated the first-ever detailed mapping of gases and particles that affect Earth’s climate, they say.

By James E. Hansen and Makiko Sato — July 2011

The past is the key to the future. Contrary to popular belief, climate models are not the principal basis for assessing human-made climate effects. Our most precise knowledge comes from Earth’s paleoclimate, its ancient climate, and how it responded to past changes of climate forcings, including atmospheric composition. Our second essential source of information is provided by global observations today, especially satellite observations. which reveal how the climate system is responding to rapid human-made changes of atmospheric composition, especially atmospheric carbon dioxide (CO2). Models help us interpret past and present climate changes, and, in so far as they succeed in simulating past changes, they provide a tool to help evaluate the impacts of alternative policies that affect climate.

Paleoclimate data yield our best assessment of climate sensitivity, which is the eventual global temperature change in response to a specified climate forcing. A climate forcing is an imposed change of Earth’s energy balance, as may be caused, for example, by a change of the sun’s brightness or a human-made change of atmospheric CO2. For convenience scientists often consider a standard forcing, doubled atmospheric CO2, because that is a level of forcing that humans will impose this century if fossil fuel use continues unabated.

We show from paleoclimate data that the eventual global warming due to doubled CO2 will be about 3°C (5.4°F) when only so-called fast feedbacks have responded to the forcing. Fast feedbacks are changes of quantities such as atmospheric water vapor and clouds, which change as climate changes, thus amplifying or diminishing climate change. Fast feedbacks come into play as global temperature changes, so their full effect is delayed several centuries by the thermal inertia of the ocean, which slows full climate response. However, about half of the fast-feedback climate response is expected to occur within a few decades. Climate response time is one of the important ‘details’ that climate models help to elucidate.

The long lifetime of existing transportation and energy infrastructure means that continued emissions of CO2 from these sources are likely for a number of decades. This ‘infrastructural inertia’ alone is projected to produce a warming commitment of 1.3°C above the pre-industrial era. This result emphasizes that extraordinary measures will be required to limit emissions from new energy and transportation sources if global temperature is to be stabilized below 2°C.

Climate modeling has demonstrated that even if atmospheric composition was fixed at current levels, continued warming of the climate would occur due to inertia in the climate system. This form of climate change commitment has become widely recognized. Davis et al. focus attention on inertia in human systems, by asking ‘what CO2 levels and global mean temperature would be attained if no additional CO2-emitting devices (e.g., power plants, motor vehicles) were built but all the existing CO2-emitting devices were allowed to live out their normal lifetimes?”. Barring widespread retrofitting or early decommissioning of existing infrastructure, these committed emissions represent ‘infrastructural inertia’. The authors developed scenarios of global CO2 emissions from existing infrastructure directly emitting CO2 to the atmosphere for the period 2010 to 2060 (with emissions approaching zero at the end of this time period) and used the University of Victoria Earth System Climate Model to project the resulting changes in atmospheric CO2 and global mean temperature. Projections with low, mid and high emissions scenarios led to projected global average warming of 1.3°C (1.1° to 1.4°C) above the pre-industrial era. Since new sources of CO2 are bound to be built in the future in order to satisfy growing demands for energy and transportation, the committed warming from existing infrastructure makes clear that satisfying these demands and achieving the 2°C target of the Copenhagen Accord will be an enormous challenge.

Summary courtesy of Environment Canada

Two recent studies confirm that while only 25 percent of the Earth’s planetary greenhouse effect is caused by the presence of long lived greenhouse gases (particularly CO2), the natural greenhouse effect would collapse without these gases. Furthermore, CO2 concentrations are the primary control for the magnitude of this effect.

Public discussions about the natural greenhouse effect and climate sensitivity to rising CO2 concentrations often indicate a misunderstanding of the roles of long lived greenhouse gases (LLGHGs) relative to those of water vapour and cloud feedbacks within the climate system. Two new studies undertaken by scientists at the NASA Goddard Institute for Space Studies have provided some updated estimates for these roles and reinforce the central role of LLGHGs in the greenhouse effect. In one of these, a team of scientists led by Gavin Schmidt undertake a review of related scientific literature and use the radiation component of their GISS global climate model to examine the role of each of the key components of the greenhouse effect for current and 2xCO2 conditions. They find that for current conditions, water vapour represents 50% of the effect, clouds 25% and CO2 20%. The remaining five percent is due to the minor roles played by other radiation absorbers. While the total effect increases significantly under doubled CO2 conditions, the ratios essentially remain the same. The second study, led by Andrew Lacis, emphasizes the importance of the initial radiative forcing caused by CO2 and the other minor LLGHGs in sustaining the natural greenhouse effect and in causing changes in its magnitude. They show that, without this initial forcing, the greenhouse effect would collapse, leaving the Earth a frozen planet. Increases in CO2 are also the primary driver of enhanced greenhouse effects and the resulting rise in surface temperatures. That is, while the roles of water vapour and cloud effects are very important in the net greenhouse effect, they function as feedbacks rather than primary drivers of change.

Summary courtesy of Environment Canada

That is exactly what is happening with U.S. decisions regarding the climate crisis. The best available evidence demonstrates beyond any reasonable doubt that the reckless spewing of global-warming pollution in obscene quantities into the atmospheric commons is having exactly the consequences long predicted by scientists who have analyzed the known facts according to the laws of physics.

Instead, however, Professor Muller reported that his group’s preliminary results find a global warming trend “very similar to that reported by the prior groups.”

The deniers’ response was both predictable and revealing; more on that shortly. But first, let’s talk a bit more about that list of witnesses, which raised the same question I and others have had about a number of committee hearings held since the G.O.P. retook control of the House — namely, where do they find these people?