Science CulminatingBenjamin KuipersINTRODUCTIONClimate change has greatly affected the Earth and its inhabitants, with catastrophes such as droughts, intense floods, increase in storm severity, etcetera. But easily one of the worst products of climate change would be the impending rising sea-level. This is an issue that will displace millions, leaving coastal areas and communities submerged and uninhabitable.
WHAT IS HAPPENINGOver the last hundred years, satellite measurements have told us that the average sea level height or Global Mean Sea Level has risen by four to eight inches. However, the yearly rate of the past twenty years has been point one-three inches a year, almost twice the average speed of the previous eighty years.The burning of fossil fuels, as well as other human and natural activities over the last hundred years, has released tremendous amounts of heat-trapping, greenhouse-gases such as carbon dioxide into the atmosphere. These greenhouse-gas emissions have caused the Earth’s surface temperature to rise heavily, and the oceans absorb roughly eighty percent of this additional heat.WHY THIS IS HAPPENINGWhy does the Earth heating directly impact the rise in sea level? There are three main factors all contributing to this key concept. These are (i) Thermal Expansion: As water heats up, it expands–the same way molecules spread further apart in hotter conditions. Roughly 50% of the past century’s rise in sea level is attributable to warmer oceans taking up more space.(ii) The most significant of all is the melting of Polar Ice Caps and Glaciers.
Large ice formations, such as the polar ice caps and glaciers, naturally melt a small amount each summer. In winter, snow made from evaporated seawater balances out the melting, putting the ice formations in a state of equilibrium. Recently, however, growing temperatures due to global warming have led to more than average summer melting as well as less intense snowfall from late winters and early springs/summers.(iii) The most significant of the ice formations; West Antarctica and Greenland: As well as the glaciers and ice caps, increased heat is causing the enormous ice blankets over Antarctica and Greenland to melt at an accelerated speed. According to National Geographic, glaciers that flow into the ocean (Antarctica and Greenland) are the most susceptible to climate change’s effects. Scientists believe melted water from above and seawater from below is seeping beneath Antarctica’s and Greenland’s ice sheets, effectively lubricating ice sheets and allowing them to move more quickly into the sea.
Hotter sea temperatures are causing the large ice shelves that extend out from Antarctica to melt from below, loosen, and then eventually break off. The glaciers and ice sheet of Greenland cover a land area greater than the European countries of Germany, France, Spain and Italy combined. If all Greenland’s ice melted, sea levels would rise by roughly 23 feet. The number of people living in countries less than thirty feet above the sea level is six-hundred and thirty-four million.WHAT THIS MEANSWhen sea levels rise rapidly, as they have been doing, even a small increase can have devastating effects on coastal habitats. As seawater reaches farther inland, it can cause destructive erosion, wetland flooding, aquifer and agricultural soil contamination, and lost habitat for fish, birds, and plants. According to the WWF (World Wildlife Foundation) that even a sea level rise of 3 feet will cost 28 trillion dollars of US dollars to world economies.
When large storms hit land, higher sea levels mean bigger, more powerful storm surges that can strip away everything in their path.In addition, hundreds of millions of people live in areas that will become increasingly vulnerable to flooding. Higher sea levels would force them to abandon their homes and relocate. Low-lying islands could be submerged completely.HOW HIGH WILL IT GO?Most predictions say the warming of the planet will continue and is likely to accelerate. Oceans will likely continue to rise as well, but predicting the degree to which they will rise is an inexact science. The Intergovernmental Panel on Climate Change says we can expect the oceans to rise between 11 and 38 inches (28 to 98 centimeters) by 2100, enough to swamp many of the cities along the U.
S. East Coast. More dire estimates, including a complete meltdown of the Greenland ice sheet, place sea level rise to 23 feet (7 meters), enough to submerge London.HOW WE CAN REVERSE THESE EFFECTS