The Day After Tomorrow

The Hollywood science-fiction film The Day After Tomorrow (2004), an action-packed thriller about abrupt climate change, caught the attention of moviegoers around the world. But was this film science or science fiction? According to experts at the Ocean and Climate Change Institute and Woods hole Oceanographic Institution, the abrupt climate change depicted in the movie over a time span of just a few weeks could not happen that fast. The climate is a huge, complex interactive system involving the land, atmosphere, and oceans, and a change in ocean circulation that could trigger a large-scale climatic change would take decades. Not only can the oceans not change that fast, but also ice sheets and glaciers cannot melt in a few weeks, either.

Most of the references to abrupt climate change to scientists revolve around the disturbance of the Atlantic conveyor belt and its key impact on the north Atlantic, Europe, and the eastern United States. A cooling in these areas, however, would not cause a global cooling or a global ice age.

Scientists predict that the degree of cooling that would occur would depend on the changes in ocean circulation. If changes were to occur between now and the next 50 years, the cooling effect may be more severe than if ocean circulation changes did not happen for 50 to 100 years. The reason for this is that the longer that global warming continues to rise, its warming effects may counterbalance and then outweigh the cooling effects.

Climate experts also commented on the hurricane that swept down from the Arctic in the movie. hurricanes cannot form in the Arctic because hurricanes need heat and moisture from warm ocean waters to grow. The immense size of the storm is also impossible. No single storm system could reach the size of the northern hemisphere; the pressure gradients needed work on much smaller scales.

nor is there any need to worry about the -150° wind chill, either, they say. The lowest temperature ever recorded on Earth was in Vostock, Antarctica, on July 21, 1983: a bone-chilling -128.6°F (-89.2°C).

Alley also stresses that there may be certain climate thresholds in existence that experts have not yet discovered. Scientists do agree that unexpected changes could be devastating and have cautioned for global

Furthermore, storm surges do not arrive in the 40-foot (12-m) variety in New York, nor do they arrive as a single, giant wave. The wave in the movie more closely resembled a tsunami. Storm surges usually occur as a rise in water over a time period of several hours. According to experts, models produced by NOAA have predicted that storm surges of 20 feet (6 m) are possible in New York if a powerful hurricane hit northern New Jersey.

Mammoth chunks of ice breaking off of Antarctica do not cause tidal waves. In fact, when an ice shelf detaches from Antarctica, it does not even cause a rise in sea level because it is already floating in the ocean. In 2002, a piece of the Larsen B Ice Shelf the size of the state of Rhode Island broke off and did not cause a tsunami or any rise in sea level.

Global warming, however, does contribute to a rise in sea level in two different ways: 1) when ice on land melts and flows into the ocean, and 2) when water is heated, because it expands. This is called "thermal expansion" and is more pronounced in the mid- to polar latitudes. If the West Antarctic Ice Sheet—a huge mass of ice roughly the size of Alaska and California combined—were to melt into the ocean (a process that could take thousands of years at today's rate of global warming), sea levels could rise about 20 feet (6 m).

The bottom line is that experts do acknowledge abrupt climate change as a real phenomena that can take place in a matter of decades or less. The present state of global warming is melting the glaciers and ice sheets around the world, which is contributing to the freshening of the ocean water, most notably the North Atlantic. As far as shutting down the North Atlantic conveyor, many climatologists are in the process of researching and modeling it, in search of a reliable prediction of what Earth's climate will be like—the day after tomorrow.

Source: Woods Hole Oceanographic Institution reductions of carbon emissions as a way to slow global warming. Further research is also needed, as it takes time to understand the extreme complexity of the climate system.

The U.S. National Research Council has recommended that societies also need to develop plans to be able to cope with abrupt climate change before the next climate "surprise" occurs. They have suggested that communities plant trees in order to stabilize soil in the event of drought so that winds do not carry away dry soil, as they did in the dust bowl of the 1930s in the U.S. Midwest. Regions should also plan for and manage their water resources wisely so that if a drought occurred, communities would be prepared.

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