The Effects of CO2 Emissions on Climate Change

This page contains links to pages science reporting on the effects of CO2 on the climate of a planet.

"Currently, carbon dioxide levels are just above 400 parts per million (ppm), up approximately 120 ppm in the last 150 years and rising about 2 ppm each year," said Ken MacLeod, a professor of geological sciences at MU. "In our study, we found that during the Late Cretaceous Period, when carbon dioxide levels were around 1,000 ppm, there were no continental ice sheets on earth. So, if carbon dioxide levels continue to rise, the Earth will be ice-free once the climate comes into balance with the higher levels."

Under elevated carbon dioxide levels, wetland plants can absorb up to 32 percent more carbon than they do at current levels, according to a 19-year study published in Global Change Biology from the Smithsonian Environmental Research Center in Edgewater, Md. With atmospheric CO₂ passing the 400 parts-per-million milestone this year, the findings offer hope that wetlands could help soften the blow of climate change.

An instrument near the summit of Mauna Loa in Hawaii  recorded a long-awaited climate milestone today: the amount of carbon dioxide in the atmosphere there has exceeded 400 parts per million (ppm) for the first time in 55 years of measurement—and probably more than 3 million years of Earth history.

More carbon dioxide is released from residential lawns than corn fields according to a new study. And much of the difference can likely be attributed to soil temperature. The data, from researchers at Elizabethtown College, suggest that urban heat islands may be working at smaller scales than previously thought.

Global carbon dioxide (CO₂) emissions are set to rise again in 2012, reaching a record high of 35.6 billion tonnes -- according to new figures from the Global Carbon Project, co-led by researchers from the Tyndall Centre for Climate Change Research at the University of East Anglia (UEA).

Feeding the world releases up to 17,000 megatonnes of carbon dioxide into the atmosphere annually, according to a new analysis released October 30 by the CGIAR Research Program on Climate Change, Agriculture and Food Security (CCAFS). But while the emissions "footprint" of food production needs to be reduced, a companion policy brief by CCAFS lays out how climate change will require a complete recalibration of where specific crops are grown and livestock are raised.

Researchers from the Massachusetts Institute for Technology have shown that the material strength and fracture toughness of ice are decreased significantly under increasing concentrations of CO₂ molecules, making ice caps and glaciers more vulnerable to cracking and splitting into pieces, as was seen recently when a huge crack in the Pine Island Glacier in Antarctica spawned a glacier the size of Berlin.

The study also shows that the observed warming in the North Atlantic during the 20th century cannot be explained by the solar and volcanic activity alone. In the model, the increased emissions of CO2 and other well-mixed greenhouse gases to the atmosphere since the onset of the industrial revolution have to be included in order to simulate the observed temperature evolution.

A new peer-reviewed scientific study counters a major premise of global warming theory, concluding carbon dioxide did not end the last ice age.

Using computer modeling to integrate forest canopy measurements and remote satellite data, researchers found that autumn warming greatly increases soil decomposition and significantly reduces carbon dioxide uptake.

India will become the third-biggest emitter of carbon dioxide by 2015 and rapid economic growth of the country and its neighbour China will have devastating consequences for the world's energy supply unless the two Asian giants make efforts to curb demand and greenhouse gas emissions, the International Energy Agency warned on Wednesday.

To discover how the situation has changed since the last ice age, researchers studied 20,000-year-old mud samples from the sub-Arctic Pacific Ocean lying approximately three feet below the present sea bed. They found the water in the ocean’s depths exchanged less CO2 with the atmosphere than it does at present, while capturing more atmospheric CO2 than the water does today, suggesting as oceans become warmer as a result of climate change they release more carbon dioxide into the atmosphere. [posted by NewsDaily on January 24, 2008]

Global temperatures could be less sensitive to changing atmospheric carbon dioxide (CO2) levels than previously thought, a study suggests.http://www.sciencedaily.com/releases/2012/12/121202164059.htm?utm_source=feedburner&utm_medium=email&utm_campaign=Feed%3A+sciencedaily+%28ScienceDaily%3A+Latest+Science+News%29

“The system is finely in tune,” says Caldeira. “That one or two percent imbalance works out to an average imbalance in natural carbon dioxide emissions that is thousands of times smaller than our current emissions from industry and the destruction of forests.”

Before humans began burning fossil fuels, there was an eons-long balance between carbon dioxide emissions and Earth’s ability to absorb them, but now the planet can’t keep up, scientists said on Sunday. [posted by NewsDaily on April 27, 2008]

Climatologists from Bern University said their study also showed that concentrations of greenhouse gases are increasing at a faster rate, Swissinfo.com reported. For example, the concentration of carbon dioxide increased by 31 parts per million during one 1,600-year interval in the pre-industrial period — its fastest growth before the industrial age — and went up by the same amount in the past 20 years. [posted by NewsDaily on February 1, 2008]

Australian and international researchers have found that weakening of the land and ocean sinks is causing carbon dioxide to accumulate in the atmosphere faster than expected.

The basic proposition behind the science of climate change is so firmly rooted in the laws of physics that no reasonable person can dispute it. All other things being equal, adding carbon dioxide (CO₂) to the atmosphere—by, for example, burning millions of tons of oil, coal and natural gas—will make it warm up. That, as the Nobel Prize–winning chemist Svante Arrhenius first explained in 1896, is because CO₂ is relatively transparent to visible light from the sun, which heats the planet during the day. But it is relatively opaque to infrared, which the earth tries to reradiate back into space at night. If the planet were a featureless, monochromatic billiard ball without mountains, oceans, vegetation and polar ice caps, a steadily rising concentration of CO₂ would mean a steadily warming earth. Period.

Researchers measured an additional 16.2 billion tons of carbon dioxide (CO₂) — a byproduct of fossil fuel burning — and 12.2 million tons of methane in the atmosphere at the end of December 2008. This increase is despite the global economic downturn, with its decrease in a wide range of activities that depend on fossil fuel use.

Most of the carbon dioxide emitted by human activity does not remain in the atmosphere, but is instead absorbed by the oceans and terrestrial ecosystems. In fact, only about 45 percent of emitted carbon dioxide stays in the atmosphere.

According to current best estimates of climate sensitivity, the amount of CO2 and other heat-trapping gases added to Earth’s atmosphere since humanity began burning fossil fuels on a significant scale during the industrial period would be expected to result in a mean global temperature rise of 3.8°F — well more than the 1.4°F increase that has been observed for this time span. Schwartz’s analysis attributes the reasons for this discrepancy to a possible mix of two major factors: 1) Earth’s climate may be less sensitive to rising greenhouse gases than currently assumed and/or 2) reflection of sunlight by haze particles in the atmosphere may be offsetting some of the expected warming.

A new estimate of the feedback between temperature and atmospheric carbon dioxide (CO2) concentration has been derived from a comprehensive comparison of temperature and CO2 records spanning the past millennium.

In a paper published November 21 in Nature Geoscience, the authors found that despite the major financial crisis that hit the world last year, global CO2 emissions from the burning of fossil fuel in 2009 were only 1.3 per cent below the record 2008 figures. This is less than half the drop predicted a year ago.

Recently, destructive peat fires plagued the Moscow region. In the late 1990s, severe Indonesian fires in drained peatlands released carbon equivalent to 40 per cent of annual global fossil fuel emissions.

A drop in carbon dioxide appears to be the driving force that led to the Antarctic ice sheet’s formation, according to a recent study led by scientists at Yale and Purdue universities of molecules from ancient algae found in deep-sea core samples.

The new study created a computer simulation of CO₂ emissions in the Salt Lake Valley using three sources of information:

• CO₂ measurements from three sites -- the University of Utah, downtown Salt Lake City and Murray, Utah, about halfway south down the valley's length.
• Data from weather stations in the valley, crunched through weather forecasting software used to predict wind and air circulation.
• Satellite data showing what parts of the valley are covered by homes, other buildings, trees, agriculture and so on.

"We found that decades-old carbon in surface soils is released to the atmosphere faster when temperatures become warmer," said lead author Francesca Hopkins, a doctoral researcher in UCI's Earth system science department. "This suggests that soils could accelerate global warming through a vicious cycle in which human-made warming releases carbon from soils to the atmosphere, which, in turn, would warm the planet more."

Based on Hansen's temperature analysis work at the Goddard Institute for Space Studies, Earth's average global surface temperature has already risen .8 degrees Celsius since 1880, and is now warming at a rate of more than .1 degree Celsius every decade. This warming is largely driven by increased greenhouse gases in the atmosphere, particularly carbon dioxide, emitted by the burning of fossil fuels at power plants, in cars and in industry. At the current rate of fossil fuel burning, the concentration of carbon dioxide in the atmosphere will have doubled from pre-industrial times by the middle of this century. A doubling of carbon dioxide would cause an eventual warming of several degrees, Hansen said.

In spite of the rise in atmospheric CO₂ concentration of about 70 parts per million by volume and in global temperatures of about 0.50°C over the last 6 decades, the All India Rainfall index does not yet show the expected increase in rainfall. The reviewers Andrew Turner from the Department of Meteorology at the University of Reading and H. Annamalai from the International Pacific Research Center at the University of Hawaii at Manoa give several reasons for why the region's observed rainfall has not yet increased, among them are inconsistent rainfall observations, decadal variability of the monsoon, the effects of aerosols resulting from industrialization, and land-use changes.

Research scientist Sassan Saatchi of NASA's Jet Propulsion Laboratory, Pasadena, Calif., participated in the study, published June 21 in the journal Science. The team, led by researchers from Winrock International, an environmental nonprofit organization in Little Rock, Ark., also included scientists from Applied GeoSolutions, Durham, N.H.; and the University of Maryland, College Park. They combined satellite data on gross forest loss and forest carbon stocks to track emissions from deforestation in the world's tropical forests. The resulting gross emissions estimate of 0.81 billion metric tons of carbon emitted per year is approximately one third of previously published estimates, and represents just 10 percent of the total global human-produced carbon emissions over the time period analyzed (2000 to 2005).

In what might be the first study to report continuous measurements of net CO₂ exchange of urban vegetation and soils over a full year or more, scientists from UC Santa Barbara and the University of Minnesota conclude that not only is vegetation important in the uptake of the greenhouse gas, but also that different types of vegetation play different roles.

The new Harvard-Nanjing study goes deeper, however, constructing a "bottom-up" emission inventory that is specific to China's energy and technology mix. It combines the results of Chinese field studies of CO₂ emissions from diverse combustion processes with a plant-by-plant data set for power generation, independent research on transportation and rural biomass use, and provincial-level energy statistics for the remaining sectors.

The new evidence supports an emerging view that although forests remove a substantial amount of carbon dioxide from the atmosphere, much of the carbon is being stored in living woody biomass rather than as dead organic matter in soils.

Global emissions of carbon dioxide (CO₂) -- the main cause of global warming -- increased by 3% last year, reaching an all-time high of 34 billion tonnes in 2011. In China, the world's most populous country, average emissions of CO₂ increased by 9% to 7.2 tonnes per capita. China is now within the range of 6 to 19 tonnes per capita emissions of the major industrialised countries. In the European Union, CO₂ emissions dropped by 3% to 7.5 tonnes per capita. The United States remains one of the largest emitters of CO₂, with 17.3 tones per capita, despite a decline due to the recession in 2008-2009, high oil prices and an increased share of natural gas.

"Our analyses of ice cores from the ice sheet in Antarctica shows that the concentration of CO₂ in the atmosphere follows the rise in Antarctic temperatures very closely and is staggered by a few hundred years at most," explains Sune Olander Rasmussen, Associate Professor and centre coordinator at the Centre for Ice and Climate at the Niels Bohr Institute at the University of Copenhagen.

Using 15 of the most robust proxy records of marine and terrestrial climate, Das Sharma et al. employ new statistical and mathematical techniques to quantify the interactions among climatic parameters and to investigate which of these parameters could be the primary drivers of climate change during MIS 11. The authors find that atmospheric CO₂ concentration was indeed the primary driver of both terrestrial and marine climate: Sea surface temperature and the isotopic makeup of carbon in terrestrial and marine reservoirs responded "instantaneously" (i.e., within 1,000 years) to changes in atmospheric CO₂ content.

Earth's oceans, forests and other ecosystems continue to soak up about half the carbon dioxide emitted into the atmosphere by human activities, even as those emissions have increased, according to a study by University of Colorado and NOAA scientists published August 1 in the journal Nature.

The results were surprising. Substantially more carbon compounds where discharged by the river than the annual procedure of pre-harvest burning of sugar cane plantations could produce. "When we plotted the results from the samples against time and compared this pattern with the amount of precipitation and the occurrence of fires, the relation became obvious. The charred carbon must have originated from the slash and burn period from much earlier times."