Three things you should know:
1) Increasing global temperatures cause sea level rise in two distinct ways. One way is through expansion, since the volume of the oceans expand as the water warms. Another takes place when glaciers of all sizes melt, because they add extra water to the sea.
2) Computer models are used to predict how much the melting ice will contribute to future sea level rise, but uncertainty in these models makes it difficult to pinpoint a narrow range for sea level rise.
3) The melting of small mountain glaciers and icecaps from all continents is expected to contribute about 12 cm to global sea level rise by 2100, according to a new study.
The Tabuchet glacier on La Meije in the French Alps is an example of a small glacier, many of which are melting and contributing to sea level rise. Credit: Gilles 92, flickr
Small mountain glaciers and ice caps, like those scattered among the uppermost regions of the Rocky Mountains, make up only about one percent of the world’s total ice cover. But while the massive continental ice sheets in the Arctic and Antarctic dwarf the small mountain glaciers, researchers say that melting from these smaller glaciers contributes a disproportionately large amount to global sea level rise, and could account for as much as 25 percent of sea level rise by 2100.
Until now, most research on how much melting ice may contribute to rising sea levels has neglected the small glaciers.
Three Things You Should Know
1) The number of heat waves in the U.S. and around the world has increased, a likely consequence of rising average global temperatures.
2) Heat waves can cause heat-related illnesses and can increase the risk of death.
3) When preparing for a coming heat wave, policy makers should consider different communities’ needs and the socioeconomic links between heat waves and deaths, says a new study.
New Yorkers keep cool in a local fountain during a heat wave in the summer of 2010. Credit: Vasilios Sfinarolakis, flickr.
In the past few weeks, most of the country has been feeling the full force of winter, with both frigid weather and some big snowstorms. But less than six months ago, record-breaking heat waves struck many parts of the United States and around the world, as many as 19 countries set new all-time record high temperatures during the year. With such extreme temperatures can come heat-related health problems, and many regions of the world are just beginning to look at how to be better prepared to face more frequent and deadly heat waves in the future.
A new study published in the journal Global Environmental Change examines how important socioeconomic factors could be to planning for heat-related health problems. According to this review, a growing collection of data suggests that people’s susceptibility to heat isn’t limited to the outside temperatures, air quality, and their age — even though these are the kinds of factors that guide many heat wave emergency response plans. Research shows that the community a person l...
Climate In Context
Three things you need to know
-- The U.S. Department of Energy projects that it is possible for the U.S. to get 20 percent of its electricity from wind energy by 2030, if there is a major investment in building the needed infrastructure.
-- Some of the country’s best wind energy resources are found blowing over the rich agricultural lands of the Midwest.
-- Wind turbines set amidst agricultural land in the Midwest refresh the air around the plants, and now researchers are studying how changes in airflow will impact corn and soybean crops.
Wind turbines such as these have been erected across the Midwest recently. Credit: flickr/WindeBabe.
When wind turbine blades absorb energy from the wind to generate electricty, they also channel some airflow down towards the ground. Now, researchers are getting a sense of how air currents change at the ground level near large turbines, fueling speculation about how this might affect crops growing nearby.
Last week at the American Geophysical Union’s annual meeting in San Francisco, Eugene Takle, an agricultural meteorologist from Ames Laboratory at Iowa State University, shared new data (not yet published) showing that at ground level where crops are growing, areas below wind turbines experience more exchange of air than where there aren’t any turbines. Last summer, Takle and his collaborators sampled the air within cornfields that also contain large wind turbines. By measuring the temperature changes, moisture levels, carbon dioxide (CO2) concentrations and wind speeds of...
Three things you need to know:
-- In the past decade, climate change has caused wildfires in Alaskan forests to burn more often and more severely.
-- These fires are burning layers of moss and peat in the soil, which releases greenhouse gases that had been stored over decades and centuries and even millennia.
-- These forests, which previously stored immense quantities of carbon, are now releasing more than they are saving.
Wildfires burning in Alaska's boreal forests are now releasing more greenhouse gases than they are storing. Credit: US Fish and Wildlife Service.
During the past decade, forests in Alaska and northern regions of Canada have become more susceptible to wildfires. With climate changes leading to warmer and drier spring and summer seasons, the growing seasons have become longer, the ground has been drying out, and more of the permafrost that lies beneath the forest floor has been melting. It all makes for more conducive burning conditions. Now, a new study shows that Alaska wildfires are also burning deeper into the ground and releasing immense quantities of greenhouse gases that had been stored away in the soil for years.
According to research published this week in Nature Geoscience, Alaska wildfires burning later in the summer burn deeper, freeing up more soil carbon, than early season fires. As all this biomass burns, and then smolders, it releases vast amounts of carbon dioxide (CO2) and other greenhouse gases.
“A fire that burns for a very brief time, sometimes hours, can release carbon that has been stored in the soil for decades, or even centuries,...
Three things you need to know:
-- New research shows that some coastal marshlands will not survive rapid sea level rise to 2100, though some may be able to adapt if sea levels change slowly.
-- Some amount of sea level rise by 2100 is inevitable, scientists say, but the possible range —between one and five feet — heavily depends on future greenhouse gas emissions.
-- The survival of coastal marshlands could play an important role in absorbing a lot of the carbon dioxide (CO2) emitted by human activity.
Scientists often point to sea level rise as one of the unavoidable consequences of global warming. They are not exactly sure how much the ocean will rise in the next 100 years — or how quickly — but they expect somewhere between one to five foot increase by the end of this century. Because there is no way to avoid some sea level rise as global temperatures go up, researchers are now trying to better understand how coastlines will respond as the waters creep upward.
Anticipating how wetlands and marshes along the coast might adapt turns out to be particularly tricky. Marshes can rise or sink in response to changes in sea level, depending on how much sediment is in the area and how easily it can move around. Yet even though wetlands have some ability to adjust themselves, a new study shows that if the sea rises rapidly in the next century, most marshy areas won’t have time to adapt and may be lost altogether.
According to research c...