Washington, D.C.--The climate warming caused by a single carbon emission takes only about 10 years to reach its maximum effect. This is important because it refutes the common misconception that today's emissions won't be felt for decades and that they are a problem for future generations.
For the first time, a study conducted by Carnegie's Katharine Ricke and Ken Caldeira has evaluated how long it takes to feel the maximum warming effect caused by a single carbon emission. Their work is published in Environmental Research Letters.
"A lot of climate scientists have intuition about how long it takes to feel the warming from a particular emission of carbon dioxide," Ricke said. "But that intuition might be a little bit out of sync with our best estimates from today's climate and carbon cycle models."
Many climate model simulations focus on the amount of warming caused by emissions sustained over decades or centuries, but the timing of temperature increases caused by particular emission has been largely overlooked. Ricke and Caldeira sought to correct that by combining the results from two large modeling studies one about the way carbon emissions interact with the global carbon cycle and one about the effect of carbon on the Earth's climate used by the Intergovernmental Panel on Climate Change.
They found that actions taken to avoid emissions today would be felt within the lifetimes of the people who acted, not just by future generations.
"CO2 emissions cause global temperatures to increase for about a decade, but then temperatures stay high for a long time," Caldeira said. "This means if we avoid an emission, we avoid heating that would otherwise occur this decade. This will benefit us and not just our grandchildren. This realization could help break the political logjam over policies designed to reduce greenhouse gas emissions."
The authors note, however, that while the warming caused by a single emission reaches a maximum quickly, damage caused by this warming can play out over longer periods, including effects of sea level rise and harm to ecosystems caused by sustained warming.
The Carnegie Institution for Science (carnegiescience.edu) is a private, nonprofit organization headquartered in Washington, D.C., with six research departments throughout the U.S. Since its founding in 1902, the Carnegie Institution has been a pioneering force in basic scientific research. Carnegie scientists are leaders in plant biology, developmental biology, astronomy, materials science, global ecology, and Earth and planetary science.