It's Getting Hotter In Here
Climate change was the gigantic, world-altering elephant in the room for most of the year. November 2012 was one of the warmest Novembers on record, and it was also the 333rd consecutive month where global temperatures were warmer than average.
“The last time Earth had a below-average November global temperature was in 1976, and the last below-average month of any kind was February 1985 -- during the Reagan administration, when the cost of a first-class stamp was 20 cents,” Weather Underground meteorologist Jeff Masters wrote in a Dec. 18 post.
Meanwhile, other records were shattered this year when Arctic sea ice reached record lows. In late August, just 1.58 million square miles of sea ice covered the Arctic Ocean, the smallest such area ever observed by NASA satellites since the space agency began monitoring the Earth's polar ice caps 30 years ago. The previous record of 1.61 million square miles was set in mid-September 2007. The 2012 sea ice coverage was smaller by 27,000 square miles, an area slightly bigger than the state of West Virginia.
“In the context of what's happened in the last several years and throughout the satellite record, it's an indication that the Arctic sea ice cover is fundamentally changing," National Snow and Ice Data Center research scientist Walt Meier said in a statement in August.
Some scientists fear that the loss of sea ice coverage will accelerate global warming, as the increasing amount of open water will lower the average reflectivity of the planet and cause the Earth to retain more energy from the sun.
Superstorms: The New Normal?
The October surprise of Hurricane Sandy knocked out power throughout the Eastern Seaboard and devastated communities from New Jersey to the Caribbean, killing more than 200 people along the way. Though it was only a Category 2 storm at its peak, Sandy was an unusual meteorological beast and did far more damage in some areas than expected.
Sandy was one of the most expansive storms on record. As she approached the East Coast, instruments found tropical storm-force winds extending 520 miles from her center, whipping up an area of seas 1,030 miles across.
Usually, hurricanes start heading out to sea and dissipate before they reach the Northeastern U.S. But a strong ridge of high pressure near Greenland forced Sandy to take an unusual left turn back toward the East Coast and combine with a developing nor'easter, similar to how a cold front pushed Hurricane Grace back in 1991, leading to the so-called “Perfect Storm.”
Though this year Sandy is considered an unusual storm, in the years to come, climate change could mean more of these Frankenstorms, some experts say.
“It's a matter of probabilities,” Weather Underground meteorologist Jeff Masters said in an October phone interview. “When you add more heat energy to the ocean, you have more energy available to power strong storms. We've now made it possible to have something we've never seen before.”
Most scientific observations show that the oceans are heating up, and late-season hurricanes seem to be occurring more and more in recent years. Some researchers also think there may be a link between climate change and changes to the jetstream flowing above North America, which could mean more blocking ridges like the one that corralled Sandy back toward the East Coast.
The jetstream doesn't flow in a straight line -- it has bulges and loops. Southward bends that make U-shapes create areas of low pressure called troughs, and northward bends like horseshoes make high-pressure areas called ridges. Since the jetstream itself is a product of the temperature difference between the Earth's equator and the poles, it's thought that warmer Arctic waters could destabilize the jetstream as we know it, making more and more of these bulges and loops in new places.
In one analysis, Rutgers University researcher Jennifer Francis outlines how an unusually deep trough hanging over the U.S. East Coast and Western Europe during the 2009-2010 and 2010-2011 winters brought snow-storms and frigid cold. Conversely, while the Northeast may have had an unseasonably warm winter in 2011-2012 thanks in part to northward-bulging ridges in the jetstream, the phenomenon is not always without consequences.
“While it’s difficult to point the finger at Arctic amplification in causing any of these weather events, they are the types of phenomena that are expected to occur more frequently as the world continues to warm and the Arctic continues to lose its ice,” Francis wrote in March.
It's Not All Bad News
While climate change may be hovering malevolently on the horizon, the Earth still manages to amaze and delight. No matter how far humans spread across the globe, we are constantly discovering new kinds of animals on the planet.
This year, 33 new kinds of trapdoor spider were discovered in the American Southwest, including one species named for the President, Aptostichus barackobamai. In Hungary, paleontologists found the fossilized remains of a previously unknown freshwater sea beast, which has since been dubbed Pannoniasaurus.
Mexican and Peruvian biologists announced in 2012 that they had found eight new kinds of mammal in a Peruvian wildlife sanctuary. The newly discovered critters include a new species of night monkey, a new kind of common shrew oppossum, and the “enigmatic porcupine,” with quills much longer than other porcupines.
And while space might seem like the final frontier, scientists aren't quite done exploring Earth just yet. In February, Russian scientists became the first to make contact with Lake Vostok, a body of water that lies below more than 12,000 feet of ice in Antarctica. Huge subglacial bodies like Lake Vostok, sealed for millions of years beneath the ice, are thought to contain clues to the Earth's climatological and geological history and could yield some strange new lifeforms as well.
“These are indeed good times to be a polar scientist!" Montana State researcher John Priscu told National Geographic News.
That prediction should probably hold up in 2013 as well, though we can probably expect the news from the South Pole at the end of next year to be slightly more cheerful than the news from the North.