In the past couple of years, massive chunks of ice have broken off of Antarctica, stoking fear that the polar ice caps -- the North and South poles, Arctic and Antarctic -- might one day completely collapse.
Vulnerable and rapidly changing, Antarctica alone is already contributing a third of the total rise in global sea level.
Needless to say, monitoring the state of the ice caps is particularly important.
That's why NASA is keeping a close eye on the polar ice caps. But this time, the agency is doing so right here from earth. SmartPlanet interviewed Steve Hipskind, chief of NASA's AMES Earth Sciences division, about NASA's mission, called Operation Ice Bridge.
This past February, NASA's satellite for monitoring climate change from space -ICESat-1- ended. (ICESat stands for Ice, Cloud and land Elevation Satellite. A second one will be launched in five years).
To kill time until then, the agency came up with Ice Bridge.
The operation is the "largest airborne survey of Earth's polar ice ever conducted," according to the agency. It will give us a three-dimensional idea of what is happening to the polar ice caps.
To pull off this mission, the agency has been using NASA's DC-8 aircraft to monitor the health of the glaciers and sea ice, hoping to keep tabs on global warming. The seats of the plane were removed to make room for scientific instrumentation.
Recently, the plane arrived in Punta Arenas, Chile, so it could begin to collect data over parts of Antarctica.
For a complete overview, be sure to watch the video.
Here are some excerpts from the interview:
SmartPlanet: What happened to IceSat-1? And how did Operation Ice Bridge begin?
SH: We realized we needed to maintain the continuity of the measurements of the polar ice caps to monitor what was going on with climate change. Although IceSat 1 exceeded its design lifetime, it ended operations earlier this year in February and we realized we needed to replace those operations.
We didn't have our next satellite mission scheduled until 2015. And we really needed to fill in the gaps in fact. The thing that made the most sense was to just go after these measurements with the aircraft.
Operation Ice Bridge is basically the five-year, NASA airborne campaign to fill in the data over the polar ice caps between the loss of the first IceSat and the launch of IceSat-2.
SmartPlanet: Can you tell us more about Operation Ice Bridge?
SH: We are basically going up to the Arctic and the Antarctic on an annual basis. Currently, we are using what we call the conventional aircraft. We have just started flying a very large un-piloted aircraft, which allows us to have a much longer flight duration.
We can cover more ground, but it also adds a level of safety so we are not putting people in harms way. Some of the places we go to have some of the most severe climates on the planet.
So what you see behind me is actually what we call the Sierra Aircraft. It is a very small un-piloted aircraft. But NASA is all about developing the technologies to make these observations.
SmartPlanet: What information can a plane be sent out to observe?
SH: What satellites give you is the global perspective. They can take measurements on a continuing basis. With the aircraft, we have to be much more focused as the areas don't cover as wide as a geographical area. But what we can do with the aircraft is go into areas that we have seen changing the most rapidly and then get a much more detailed, more spacial and temporal measurements over specific areas of the ice.
We are particularly flying over Antarctica and looking at the ice glaciers that have been changing most rapidly. Those glaciers are flowing into the ocean and the concern right now is that some of the glaciers seem to be accelerating in their flow and losing ice volume in the process.
SmartPlanet: Why are you looking to measure the volume of the ice?
SH: The key data we are collecting is the total volume of ice. By making measurements from year to year, we are looking at the time rate of change on what's going on with the ice. You know if the ice is accumulating or if it is melting.
SmartPlanet: What is DC-8? Can you tell me more about the mission?
SH: The DC-8 is our flying laboratory. It is a very large commercial aircraft. We basically take out all of the seats and replace it with scientific instrumentation.
On this mission, we have a variety of laser instruments. There are laser altimeters. We can get very accurate measurements of what the ice surface topography is, so we can look for changes from year to year. But we have a variety of radar instruments that actually penetrate the ice and look at the underlying surface topography that is underneath the ice and that is key because we need to know what the surface of the ground is so we can feed that into computer models.
The DC-8 is a unique platform in that it is highly modified. It has windows on the belly of the aircraft as well as on the top of the aircraft. So we have instruments that we can look down and look up. In the case of these missions, we are really looking down on the ice. We also use window ports to bring in air samples on other missions so at times the DC-8 looks like a Christmas tree because it has so many sensors hanging outside of the aircraft.
SmartPlanet: What is the point of Operation Ice Bridge?
SH: We hope to understand the details of what is going on in both the Arctic and Antarctic to really understand the impact of warming temperatures and how that is going to impact the ice sheets. The polar caps have the largest reservoir of fresh water on the planet. If you start melting that from the surface of the land, the concern is that you are going to raise the sea level.
Photo: NASA/Tom Tschida