But where does that extra water go? It doesn't spread out evenly across the globe, McInnes said. Globally, there are two main factors — thermal expansion and the gravitational pull of ice sheets. With thermal expansion , ocean currents redistribute heat, which moves cold and warm water around. Atmospheric winds can also depress and raise oceans, she added. Moreover, those wind patterns are also changing as the planet warms, Live Science previously reported.
When gigantic ice sheets melt, they don't just simply add water to the ocean. Mass attracts mass. The Antarctic and Greenland ice sheets are so large that their masses exert a gravitational pull on the sea around them, Austermann said.
It was not feasible for researchers to inspect every drainage basin, or examine water volume for every river across the globe. But they could try to find changes in weight around Earth. Five millimeters of global ocean water weighs about 1. Gravity exerts more pull on things that weigh more, so the scientists thought they could use the gravity measurements to locate the weight missing from the oceans. This idea that you can weigh a continent or weigh the ocean from outer space is kind of cool.
By looking at gravity measurements of oceans and land around the globe, the researchers could spot areas that weighed more in Indeed, torrential rains had fallen over Southeast Asia, parts of South America, and eastern Australia, which suffered its worst floods in more than one hundred years.
They now know that thermal expansion only accounts for 10 to 20 percent of these kinds of sea level changes. We really needed all three to be sure that this was caused by changes in mass and not by thermal expansion. These more extensive observations have also proven that the sea level drop was only temporary.
Boening, C. Willis, F. Fasullo, who was trying to balance out the Earth's "water budget," sought an explanation for where that water, normally ocean bound, might have ended up. Now he believes he has one. His paper explaining the sea-level drop was recently accepted into the journal Geophysical Research Letters.
Fasullo worked to determine where the water might be, if it wasn't contributing to sea-level rise. In an earlier paper, the researcher and other scientists concluded it had probably gotten stored on the land somewhere. Where did the water go? In most cases, though, water that falls on land eventually drains into the ocean. Even if a whole lot of rain fell in South America's Amazon, for example, it could slow sea-level rise for only about a couple of months, as it slowly made its way to the sea.
So in order to make sea levels fall, the water had to be stored in a place where it didn't reach the ocean for a long while.
That place, it turns out, was Australia. In the continent's eastern interior, most of the rain that falls runs inland, into a salt lake called Lake Eyre -- never reaching the sea. Lake Eyre is the lowest point in Australia. It's usually a dry, salty flat. Remember to clean the whale filter every few days , so the water level starts to drop more quickly.
It's pretty similar, but there are a few small changes. And after years of trying to hold back the sea, the Netherlands are finally high and dry. No longer living with the constant threat of a cataclysmic flood, they're free to turn their energies toward outward expansion. They immediately spread out and claim the newly-exposed land. When the sea level reaches minus meters, a huge new island off the coast of Nova Scotia is exposed—the former site of the Grand Banks.
You may start to notice something odd: Not all the seas are shrinking. The Black Sea, for example, shrinks only a little, then stops.
This is because these bodies are no longer connected to the ocean. As the water level falls, some basins cut off from the drain in the Pacific. Depending on the details of the sea floor, the flow of water out of the basin might carve a deeper channel, allowing it to continue to flow out. But most of them will eventually become landlocked and stop draining. At meters, the map is starting to look weird.
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