Increased solar radiation requires an extra reduction in CO2 emissions

March 10, 2010

( -- The recently observed reduction in air pollution implies that more solar radiation reaches the Earth's surface. This could lead to a far more rapid increase in the Earth's temperature in the coming decades. These are the claims of econometricians Jan Magnus, Bertrand Melenberg, and Chris Muris from Tilburg University (The Netherlands) based on unique solar radiation data collected from weather stations between 1959 and 2002.

Their calculations show that in order to prevent an increase in global temperatures of more than two degrees we will have to reduce CO2 emissions by an additional 50 million tonnes to compensate for the increased solar radiation reaching the Earth's surface.

Everyone is familiar with the effect of CO2 emissions on the Earth’s temperature: the . Less well known is the effect of solar radiation reaching the Earth's surface, and its development over time. Besides solar fluctuations, the amount of radiation is also affected by small particles called aerosols. The more aerosols are present in the atmosphere, the less solar radiation reaches the Earth. Large quantities of aerosols actually help to cool down the Earth and to temper (‘dim’) the greenhouse effect. Without this reduction in solar radiation, the Earth’s temperature would have increased by an additional one degree during the last fifty years.

Man-made pollution affects the quantity of aerosols in the atmosphere: soot particles emitted by cars, for example, exacerbate aerosol concentrations. Measures to reduce soot emissions and the subsequent pollution have been adopted by numerous countries in recent years. These measures have reduced the quantity of aerosols in the atmosphere, thus allowing more solar radiation to reach the ’s surface, and increasing global temperatures.

The in this study uses solar radiation data over a forty-year period. Based on these data, the researchers at Tilburg University conclude that, given the increased levels of solar radiation, existing global warming forecasts for the next few years could be far too conservative. They claim that in order to compensate for the increased levels of solar radiation, greater efforts will be needed to reduce CO2 emissions. If action is not taken soon, global warming could accelerate and temperatures could soar by more than four degrees instead of the agreed maximum target of two degrees. The researchers developed a statistical model to separate the impact on temperature of the two effects. This produces different scenarios that demonstrate the effect on temperature of varying levels and .

Explore further: Pollution dims skies as well as befouling the air

Related Stories

Pollution dims skies as well as befouling the air

March 12, 2009

A University of Maryland-led team has compiled the first decades-long database of aerosol measurements over land, making possible new research into how air pollution changes affect climate change.

Stronger evidence for human origin of global warming

July 30, 2007

A recent statistical analysis strengthens evidence that human activities are causing world temperatures to rise. Most climate change scientists model Earth systems from the ground up, attempting to account for all climate ...

Faster Climate Change Predicted as Air Quality Improves

June 29, 2005

Global warming may proceed faster and be more severe than previously predicted according to research about to be published in the scientific journal Nature. Reductions in airborne particle pollution, or aerosols, as air quality ...

Aerosols May Drive a Significant Portion of Arctic Warming

April 8, 2009

( -- Though greenhouse gases are invariably at the center of discussions about global climate change, new NASA research suggests that much of the atmospheric warming observed in the Arctic since 1976 may be due ...

Study Indicates Global Warming Trend

August 10, 2005

Summers are getting sunnier in Oregon, according to evidence presented today by University of Oregon physicists during the 2005 Solar World Congress in Orlando. The study is a first step toward testing and refining regional ...

Recommended for you

Sunlight stimulates microbial respiration of organic carbon

October 17, 2017

Sunlight and microbes interact to degrade dissolved organic carbon (DOC) in surface waters, but scientists cannot currently predict the rate and extent of this degradation in either dark or light conditions. A recent study ...


Adjust slider to filter visible comments by rank

Display comments: newest first

2.7 / 5 (3) Mar 10, 2010
A related problem: Most of the observed warming in the Arctic may be the result of soot released in East Asia and carried north by prevailing winds, reducing the albedo of the Arctic ice. This makes the Arctic warming relatively straigtforward to reverse -just improve the filters of the smokestacks in China and India- but it will also result in a regional warming that was previously masked by aerosol sunlight blocking.
2 / 5 (3) Mar 10, 2010
Case 1: All the money we have been spending on pollution controls means we need to spend more money on reducing CO2 emissions.

Case 2: Take the catalytic converters off of cars, and stop worrying about CO2.

Case 3: Choose a mix of pollution and CO2 controls that results in the "best" global temperature distribution.

I happen to favor case 3. But what is the optimal distribution? Right now we have global warming mostly at the poles, which sounds good, modulo glacier melting. Figure out how to increase snow levels in the Himalayas? That might do it. ;-)
1.7 / 5 (6) Mar 11, 2010
Catalyctic converters remove nitrous oxides etc not CO2.
Carbon Dioxide is not a pollutant. Plant growth and reproduction shuts down below 150 ppm, then everything dies. Except single cell organisms, so a lot of politicians brains will survive. That is the ones WITH a single brain cell!
1 / 5 (4) Mar 12, 2010
The article calls for an additional reduction of 50 million tonnes of CO2.

To use the words of Pielke Jnr: 'This is not going to happen!'

Sad... prepare for the worst!

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.