Why does sea level rise faster than forecast?

Why sea levels are rising faster than expected: estimates of future sea levels may be too low.

Sea level is rising faster than predicted from global warming, Bill Hay, a University of Colorado geologist explained why led to this reality.

The final IPCC report (Intergovernmental Panel on Climate Change) in 2007 has projected global sea levels to rise by about 0.2 and 0.5 m by 2100. But the sea level is now at or above the expected level of about one meter or more at the end of this century.

Or said that the models used to predict sea level rise did not mention some factors, it was these factors that pushed the sea level rise.

He will present some of the elements of the talk on November 4 at the American Geological Society meeting in Charlotte, North Carolina, USA.

One of the factors he will present regarding the Arctic Sea, another factor is the Greenland ice cap, and another factor is soil moisture and groundwater extraction.

According to him, sea level rise is related to the Arctic sea ice. Despite the fact that ice is melting in the oceans, it is not this phenomenon that increases sea level. Instead, Arctic warming is losing ice in Greenland and northern Canada. Or explain: 'As the sea ice melts, an oceanic effect releases more Arctic water, the country is then replaced by ocean currents, warmer water from the South. So it is a big heat pump that brings heat to the North Pole, " Hay said. " This is not in any model. Warm water pushes the Arctic toward ice-free water, which absorbs sunlight rather than reflecting it back into space like sea ice still does. The more water there is, the more heat is trapped in the Arctic sea water, and will warm up. '

Then there are giant ice sheets in Greenland and Antarctica. During the last ice age, sea level rose to 10m due to the melting of the entire ice. New data show that oceans rise in oceans for several centuries, according to Hay.

"You can lose most of the Greenland ice caps in a few hundred years, not thousands of years, just under natural conditions," Hay said. "Not to mention how quickly they can disappear with the carbon dioxide we are discharging into the atmosphere."

This ability was noticed when it was discovered that Greenland last year had a record of thawing. The ice stream is lubricated by its own water, which has accelerated the melting speed.

Or note: 'Ten years ago we did not know much about water beneath the Antarctic ice cap. But it is there, and it allows the tape to move - even in some difficult places due to the weight of the ice on it. '

Or explain: "It is being pushed out like a toothpaste out of a tube."

He said the underground ice mountains limit the speed of ice flowing into the sea. And no one has any idea how fast the ice will flow into the sea once the underground icebergs disappear.

Another factor leading to a rise in sea level is faster than anticipated, worldwide groundwater exploitation to reduce drought. This amount of groundwater eventually flows into the oceans.

All of these factors contribute to climate change and sea level rise.

Or said, Earth's climate seems to have some steady state. When this state is no longer available, everything becomes unstable and can change quickly.