Mar 16 2009
Gravity Satellite Launching Today
The UK is launching a new earth-orbiting satellite today that will be working to gather information about gravity and topography, and will help study climate change. This European Space Agency satellite is called GOCE, which loosely stands for Gravity Field and Steady-State Ocean Circulation Explorer. Specifically, the satellite will study and gather gravity data. This satellite is being advertised as giving us the best and most precise measurements yet of our planet’s gravitational field, from its eventual orbit, 155 miles above earth. In large part this satellite’s abilities will be used for mapping more accurately, because gravity around the world changes, believe it or not.
On Earth, the gravity ranges from 32.09 feet per second squared at the equator, to 32.25 feet per second squared at the North and South poles. That’s because the earth is not exactly round, it’s more elliptical. Extra distance from the surface to the core of the earth weakens gravity’s force, so at the equator, you are literally a little bit lighter than you would be at the poles.
The result of all this will have climate change measuring results. The global reference result this satellite will come up with is called a geoid. It’s a height reference for all points on earth, according to one of the GOCE’s gradiometer engineers. A more accurate geoid gives us better climate change research. That’s because climate and temperatures are highly affected by ocean circulation, which moves warm ocean currents to the north on the surface, and moves colder water toward the equator in deep currents. This is called, by some people, “The great conveyor”. It’s estimated this movement can take up to 1,000 years. For instance, it’s known that the Gulf Stream carries warm surface water from the Gulf of Mexico to northern Europe. That is what keeps Europe from being super cold, or going into another little ice age. If the current stops due to climate change, (and there’s a possibility of that happening) Europe would become very cold again.
So, the best climate change predictions will require extremely accurate data about how much of this cold and warm water the ocean’s conveyor moves. To know this exactly, they will need to find out the topography of the ocean floor, which also influences the directions of the major ocean currents. That’s just one climate-related application for this satellite. The GOCE data will let scientists determine whether the water levels have elevated due to melting ice caps or because of warmer temps. Another thing it will do is measure how much of the Greenland ice is moving and melting. This satellite will just provide so much more accurate scientific data on all of these things involving topography, it will be a huge help to people trying hard to predict how bad the impact of climate change will be. The closer their estimates are, the better for everyone.
The satellite launch is set for today, March 16th 2009.
More info. here.
