Monday, January 04, 2016
NASA says that burning hydrocarbons COOLs the earth
There are various sources of CO2 in the atmosphere. Breathing out is a major one. Burning hydrocarbons like coal and oil is another source. But burning hydrocarbons tend to emit aerosols such as soot in addition to CO2. What is the effect of those aerosols? NASA has finally had a stab at answering that. Their summary of their findings is below. And they find, as expected, a cooling effect from atmospheric aerosols.
Amusingly, however, they do not offer a calculation of how far aerosol effects cancel out CO2 effects -- but instead blather on about how aerosols and other cooling influences vary from region to region. That suggests to me that in some regions (China?) the aerosols have a effect at least equal to the calculated CO2 effects. So if we all returned to burning lots of coal we could cancel out any warming effects from the CO2 emitted. Goodbye global warming!
No precise calculations are of course possible as the degree to which the global temperature responds to CO2 changes is very much in dispute on both theoretical and empirical grounds. It is pretty much a number plucked out of the air -- and one that is heavily challenged by both the current temperature plateau and the even longer 1945 to 1975 plateau.
But, clearly, the attack on coal may have been entirely misconceived. Its OVERALL effects might have zero influence on global temperatures. Back to the drawing board? No. Warmists never retreat no matter how often they are shown to be overlooking things. It's faith, not science
Researchers have relied on simplifying assumptions when accounting for the temperature impacts of climate drivers other than carbon dioxide, such as tiny particles in the atmosphere known as aerosols, for example. It is well known that aerosols such as those emitted in volcanic eruptions act to cool Earth, at least temporarily, by reflecting solar radiation away from the planet. In a similar fashion, land use changes such as deforestation in northern latitudes result in bare land that increases reflected sunlight.
But the assumptions made to account for these drivers are too simplistic and result in incorrect estimates of TCR and ECS, said climate scientist Gavin Schmidt, the director of NASA's Goddard Institute for Space Studies (GISS) in New York and a co-author on the study. “The problem with that approach is that it falls way short of capturing the individual regional impacts of each of those variables,” he said, adding that only within the last ten years has there been enough available data on aerosols to abandon the simple assumption and instead attempt detailed calculations.
In a NASA first, researchers at GISS accomplished such a feat as they calculated the temperature impact of each of these variables — greenhouse gases, natural and manmade aerosols, ozone concentrations, and land use changes — based on historical observations from 1850 to 2005 using a massive ensemble of computer simulations. Analysis of the results showed that these climate drivers do not necessarily behave like carbon dioxide, which is uniformly spread throughout the globe and produces a consistent temperature response; rather, each climate driver has a particular set of conditions that affects the temperature response of Earth.
The new calculations reveal their complexity, said Kate Marvel, a climatologist at GISS and the paper's lead author. “Take sulfate aerosols, which are created from burning fossil fuels and contribute to atmospheric cooling,” she said. “They are more or less confined to the northern hemisphere, where most of us live and emit pollution. There's more land in the northern hemisphere, and land reacts quicker than the ocean does to these atmospheric changes.”
Posted by John J. Ray (M.A.; Ph.D.).