- 3918 - ICE SATELLITE - measuring the glaciers? A satellite is measuring the elevation of all the Earth's surfaces. More than a trillion measurements of Earth's height - blanketing everything from glaciers in Greenland, to mangrove forests in Florida, to sea ice surrounding Antarctica.
------------ 3918 - ICE SATELLITE - measuring the glaciers
- With
millions more observations added each day, data from NASA's Ice, Cloud and land
Elevation Satellite-2 is providing a precise global portrait of elevation and
will allow scientists to track even the slightest changes in the planet's polar
regions.
-
- The data
from ICESat-2 are really blowing our minds.
The long-awaited ICESat-2 mission, launched in September 2018, continues
the record of polar height data begun with the first ICESat satellite, which
operated from 2003 to 2009.
-
- The new
satellite provides far more measurements than its predecessor. ICESat took
approximately 2 billion measurements in its lifetime, a figure ICESat-2
surpassed within its first week.
-
- When ICESat
orbited over a rift in Antarctica's Ice
Shelf in October 2008 it recorded a handful of data points indicating a
crevasse in the ice. When ICESat-2 passed over 10 years later, it collected
hundreds of measurements tracing the sheer walls and jagged floor of the
growing rift.
-
- ICESat-2 is
taking these measurements in a dense grid across the Arctic as well as
Antarctica, recording each spot every season to track both seasonal and annual
changes in ice.
-
- In coastal
areas, in clear waters the satellite can detect the seafloor up to 100 feet
below the surface. Over forests, the satellite not only detects the top of the
canopy, but the forest floor below - which will allow researchers to calculate
the mass of vegetation in a given area.
-
- All this is
being done with six laser beams from a satellite 310 miles in space.
Getting the exact latitude, longitude, and elevation of where a photon
bounced off Earth is hard. To make sure everything is working, the science team
conducts a series of checks using data from airborne surveys, ground-based
campaigns, even the satellite itself.
-
- That
includes scientists traveling to Antarctica, where they drove modified
snow-groomers along an arc of the 88-degree-south latitude line, taking highly
accurate elevation measurements to compare with the data collected by ICESat-2
in space.
-
- Magruder
compared measurements taken in White Sands, New Mexico, with what the satellite
was tracking. In its most recent Antarctic and Arctic campaigns, NASA's
airborne Operation IceBridge flew specific routes designed to take measurements
over the same ice, at close to or exactly the same time the satellite flew
overhead.
-
- ICESat-2 is
designed to precisely measure the height of ice and track how it changes over
time. Earth's melting glaciers cause sea levels to rise globally, and shrinking
sea ice can change weather and climate patterns far from the planet's poles.
-
- Small
changes across vast areas like the Greenland ice sheet can have large
consequences. ICESat-2 will be able to measure the shift in annual elevation
across the ice sheet to within a fraction of an inch.
-
- To do
this, the satellite uses a laser altimeter - an instrument that times how long
it takes light to travel to Earth's surface and back. With that time, along
with the knowledge of where in space ICESat-2 is, and where on Earth the laser
is pointing , computer programs create a height data point.
-
- The data is
originally processed at NASA Goddard, then turned into advanced data products
that researchers will be able to use to study elevations across the globe.
-
March 15, 2023 ICE
SATELLITE - measuring the
glaciers? 3918
----------------------------------------------------------------------------------------
----- Comments appreciated and Pass it on to
whomever is interested. ---
--- Some reviews are at: -------------- http://jdetrick.blogspot.com -----
-- email feedback, corrections, request for
copies or Index of all reviews
--- to:
------
jamesdetrick@comcast.net
------ “Jim Detrick” -----------
---------------------
--- Wednesday, March 15, 2023 ---------------------------
-
No comments:
Post a Comment