global warming

PopSci.com welcomes back Dr. Bill Chameides, dean of Duke’s Nicholas School of the Environment. Dr. Chameides blogs at The Green Grok to spark lively discussions about environmental science, keeping you in the know on what the scientific world is discovering and how it affects you – all in plain language and, hopefully, with a bit of fun. Now, PopSci.com partners with The Green Grok to bring you exclusive new blog posts a week before they hit the Grok's blog. Give it a read and get in on the discussion!

Katherine Richardson is atypical. This American oceanographer is thriving at the University of Copenhagen, where she serves as Vice Dean of Science. In the genteel worlds of academia and northern Europe, she’s a straight-talker who doesn’t mince her words--uttered with a hearty Massachusetts accent.

One hundred thirty miles north of Nome, a small coastal village on Sarichef Island is feeling the effects of climate change. Shishmaref, Alaska, is falling into the sea. Rising temperatures are melting the permafrost, the layer of frozen ground beneath the surface. Without this firm base, waves have eroded the land on which Shishmaref’s villagers make their home. They must relocate their houses inland or start all over somewhere else.

Common sense says that burning a plant you regrow every year is better for the atmosphere than spewing out carbon dioxide that’s been buried underground for eons. But the truth behind biofuels and petroleum often seems to defy common sense. Neither ethanol nor gasoline bubbles out of the ground ready to put in your tank. So to figure out which one does less environmental harm, you have to calculate all the energy that goes into making it.

To predict the unpredictable: That’s the goal of a new government initiative on abrupt climate change. As the atmosphere reels under the influence of greenhouse gases, scientists fear the growing risk of dramatic environmental changes occurring within decades—far faster than current computer models predict. Ice sheets might not just melt but collapse wholesale, rapidly raising sea levels and flooding entire coastlines. Regional rain shortages could cause megadroughts that choke our water and food supply.

Ahhh, marathon Sunday. Pull on the spandex, pack up the Gu, and…strap on your ice skates? This is marathon-ing, Dutch-style. Since 1909, the Dutch have taken wildly to the frozen streets to cheer on participants in the Elfstedentocht, the 11-city, 125-mile grueling skate race completed on ice through Holland's extensive system of canals and across frozen lakes. That is, when the temperatures are low enough and the ice is thick enough.

We all know the climate is changing. But just how complicated is that process and how many factors are involved in creating this planate-wide problem? To partly answer that question, scientists have gone back nearly 90,000 years to examine Antarctic ice core samples, or, more specifically, the gas they contain. Their findings demonstrate the complex interplay between different geological players that contribute to climate changes and trends. The report implies that global warming, carbon dioxide levels, and ocean currents are not individual influencers on climate change but rather intertwined with each other. Knowing how these factors interacted many millennia ago will hopefully help scientists better understand climate change today and possibly predict future trends.

Though its cause may still be contentious for some (ahem, Sarah Palin), it is undeniable that Greenland is disappearing at a startling rate as large chunks of ice break off from the mainland and float away as icebergs. Until now, it was commonly thought that the melting and break up of mammoth glaciers was the most dramatic example of Greenland's changing landscape; however, new research shows that the real culprits are dozens of much smaller outflow glaciers dotting Greenland's coast.

A new study released by the University of Colorado at Boulder claims that a global sea rise of more than six feet by the year 2100 is nearly impossible.

The researchers used conservative, medium, and extreme scenarios for Greenland, Antarctica, and the world's smaller glaciers and ice caps. Each scenario produced a result from two feet of sea rise to no more than six feet of sea rise. When factoring in thermal expansion due to warming waters, the team concluded that the most plausible scenario would result in a total sea rise of roughly three feet to six feet by 2100.

When typhoons and hurricanes sweep through mountainous areas, they cause more than human destruction. They also physically and chemically weather the mountains they pass, taking carbon with them and burying it in the oceans in the form of sediment. This in turn allows the planet to cool. While scientists have long predicted that extreme storms cause such effects, only recently have they been able to measure just how carbon much storms take away: tons.

It's mostly bad news when it gets under your shoes, but scientists now believe cow dung may be more of a blessing in disguise than previously believed. According to a team at the University of Texas Austin, if the manure from hundreds of millions of livestock in the U.S. were to go through anaerobic digestion—a fermentation process similar to one to create compost—it could turn into an energy-rich biogas. The gas would be efficient enough to produce 100 billion kilowatt hours of electricity; that could meet about 3 percent of North America's entire consumption needs.

So it looks like it's not all gloom and doom after all. A few recent studies have managed to find the slim silver lining of climate change. Below, a look at the three small positive outcomes of global warming.

Time and time again we hear news about the danger the world's coral reefs are in. Now, the first-ever comprehensive international assessment of their conservation status reveals that the fate of coral is worse even than scientists previously believed.

Wait, now pollution is preventing global warming? That’s the conclusion of a recent study in the journal Geophysical Research Letters, which says rising temperatures seen in Europe over the last few years result as much from the reduction of air pollution as from the creation of it. The research, which looked at the effects of aerosols on climate, confirms an older concept known as global dimming, and complicates our understanding of how mankind affects the climate.

This summer, for the first time in recorded history, there may be no ice on the North Pole. In a dramatic symptom of climate change, the thick frozen layer at the pole is likely to melt away entirely, turning the top of the world from sea ice to sea water.