Sentences with phrase «middle of an ice sheet»

«Most ice cores are collected from the middle of the ice sheet where it rarely ever melts, or on the ice sheet edge where the meltwater flows into the ocean,» Karina Graeter, the lead author of the study as a graduate student in Dartmouth's Department of Earth Sciences, said in a statement.

But in the middle of an ice sheet, the ice remains close to the Ice Age temperatures at which it formed.

Not exact matches

Researchers previously used MRO's Shallow Radar (SHARAD) to map extensive underground water - ice sheets in middle latitudes of Mars and estimate that the top of the ice is less than about 10 yards beneath the ground surface.

These eight scarps, with slopes as steep as 55 degrees, reveal new information about the internal layered structure of previously detected underground ice sheets in Mars» middle latitudes.

That's because Schaefer and colleagues» data comes from a single point in the middle of Greenland, pointing to a range of possible scenarios of what happened in the past, including several that challenge the image of Greenland being continuously covered by an extensive ice sheet during the Pleistocene.

The other study in Nature — led by Joerg Schaefer of Lamont - Doherty Earth Observatory and Columbia University, and colleagues — looked at a small sample of bedrock from one location beneath the middle of the existing ice sheet and came to what appears to be a different conclusion: Greenland was nearly ice - free for at least 280,000 years during the middle Pleistocene — about 1.1 million years ago.

Pettersen's approach involved studying the types of clouds that result in snow on the ice sheet, and examining the distinct paths these clouds take before they produce snow at Summit Station, a longstanding research station located in the middle of Greenland.

In the middle of the East Antarctic Ice Sheet, the team was traveling across ice 2 miles (3 km) thick, when something strange started to happen, according to Robin Bell, a geophysicist and professor at Columbia University's Lamont - Doherty Earth ObservatoIce Sheet, the team was traveling across ice 2 miles (3 km) thick, when something strange started to happen, according to Robin Bell, a geophysicist and professor at Columbia University's Lamont - Doherty Earth Observatoice 2 miles (3 km) thick, when something strange started to happen, according to Robin Bell, a geophysicist and professor at Columbia University's Lamont - Doherty Earth Observatory.

So unless the perimeter of the Greenland ice sheet is the exact same thickness as the entire ice sheet (say 3 km on average), an area loss there, of 15 %, will produce a much smaller % volume loss, than say if this area loss were smack dab in the middle of the Greenland ice sheet.

Even if increased precipitation would thicken the ice - sheet at its middle, the speeding up of the output glaciers would dump more freshwater into the North Atlantic.

Are we sure the consequences of climate change — remember, a thick sheet of ice once covered the Middle West — must be bad?

CO2 will be anomalous near sources and terestrial sinks but this is not a concern in the middle of a huge ice sheet, unless there was an active volcanic vent nearby.

Taken together, the average of the warmest times during the middle Pliocene presents a view of the equilibrium state of a globally warmer world, in which atmospheric CO2 concentrations (estimated to be between 360 to 400 ppm) were likely higher than pre-industrial values (Raymo and Rau, 1992; Raymo et al., 1996), and in which geologic evidence and isotopes agree that sea level was at least 15 to 25 m above modern levels (Dowsett and Cronin, 1990; Shackleton et al., 1995), with correspondingly reduced ice sheets and lower continental aridity (Guo et al., 2004).

Travel to one of the poles during the winter period and place a sheet of glass, say one square metre, with a hole in the middle, say 100 square centimeters, on any flattish ice surface.

But because the ice sheet is steep at its edges but flatter toward the middle, each successive degree of warming exposes a larger area of ice to melting than the last.