We all must remember the lesson
from radar altimetry studies such as Wingham et al. 2006.
Over the sea ice field the observations include: sea ice freeboard height and hence sea ice thickness
from radar altimetry; sea ice surface temperature and sea ice drift from respectively infrared radiometer and imaging spectrometer under cloud free conditions.
Over the ocean this includes: sea surface slope and surface current, significant wave height, wind speed and sea level
from radar altimetry at about 10 km resolution: sea surface temperature under cloud free conditions from the infrared radiometer at about 300 m resolution; chlorophyll a and phytoplankton from the imaging spectrometer under cloud free conditions at about 300 m resolution.
Not exact matches
To get the biggest picture now available, Paolo and his colleagues stitched together satellite
radar altimetry data
from three consecutive and overlapping missions: the European Space Agency's (ESA's) ERS - 1 and ERS - 2 (which flew
from 1991 to 2000 and 1995 to 2011, respectively), and ESA's ENVISAT mission, which collected data
from 2002 to 2012.
Coastal
altimetry, which provides detailed wave and sea level data in the coastal zone captured by specialist instruments called
radar altimeters on board satellites, is at the heart of the project and scientists
from NOC have been at the cutting - edge of this technique.
For the last phase,
from 2003 to 2010, the researchers relied on laser
altimetry and
radar altimetry to estimate the ice elevation and map the receding ice sheet.
According to the second study, which measured changes in the thickness and height of ice using
radar and laser
altimetry instruments flown as part of NASA's Operation IceBridge campaign, the glacier lost between 984 and 1,607 feet in thickness
from 2002 to 2009.
These missions - satellite
radar altimetry projects overseen by the European Space Agency (ESA)- lasted
from 1994 to 2012, providing the researchers plenty of data that could even be overlapped and compared to ensure an accurate assessment of ice shelf thickness for more than a decade.