Climate Politix: Arctic summer sea ice

Showing posts with label Arctic summer sea ice. Show all posts

Tuesday, October 27, 2009

Arctic ice melt changing global thermostat

(Images of Arctic sea ice thickness over the years from Flickr and climatesafety.org)

While many are skeptical the Earth is warming, the Arctic is one place where the change is very evident. But some say there could be advantages to melting summer ice there – ships can take a shorter route over the top of the globe, massive oil and gas reserves are more accessible. Maybe Arctic melting isn’t all bad, they say.

But does what happens in the Arctic stay in the Arctic?

Probably not, says NOAA. Melting sea ice there seems to be affecting weather patterns around the world, according to the National Oceanic and Atmospheric Administration’s 4th annual Arctic Report Card.

Changes in the Arctic are “messing with the thermostat for the whole globe,” said Richard Spinrad, assistant administrator of NOAA. The report card compiles the work of 71 scientists in nine countries.

They found climate change was affecting the Arctic is many ways:
• Declining summer sea ice
• A shorter snow season
• Rising land temperatures
• Warming permafrost, which stores methane
• Changes in habitat and numbers of polar bears, walruses and seabirds.

Summer Arctic sea ice hit a historic low in 2007 and has come back a bit the last two summers, which has skeptics saying, “See. There’s no global warming.”

But what’s new and perhaps more important is the thinning of perennial ice, not just that which melts in the summer and then comes back in fall. The average thickness is down 2.2 feet between the 2004 and 2008.

The summer sea ice melt causes more open dark water, which absorbs heat and then sends it back into the atmosphere in fall. This cycle is sending land temps up, letting trees grow in the tundra farther north and affecting atmospheric circulation as far south as middle North America.

As old, thick sea ice goes away and is replaced by more fragile first-year-ice, new climate patterns are being set up, says oceanographer James Overland. “It changes everything,” he told ClimateWire.
• The ocean surface is warmer and less salty
• Greenland is melting
• Siberia has more runoff
• There’s less snow in North America

So, what happens in the Arctic won’t stay in the Arctic. We’d all better take notice.

To read more and see slideshow go to NOAA's Web site

(Sources: ClimateWire, NOAA)

Saturday, September 26, 2009

Global warming update is ‘wake-up call’ to nations

(Photo of retreating Athabasca Glacier from Flickr and photographer Janet.Powell)

Climate is changing faster than forecast just two years ago by the authoritative IPCC, a new UN report revealed last week.

More CO2 is going into the atmosphere, glaciers and ice sheets are melting faster, oceans are getting more acidic, and perennial droughts are more common, the UN Environment Programme update said.

Global temperatures could rise 8 degrees Fahrenheit (above pre-industrial levels), based on pledges by countries so far to cut greenhouse gas emissions – double the temperature scientists in the 2007 Intergovernmental Panel on Climate Change said would be catastrophic. Some think tipping points will come in a matter of years or decades, rather than in a century, as earlier forecast.

Degree of damage
After assessing the latest peer-reviewed science, the report said:
• CO2 in the atmosphere is growing at 3.5% a year this decade, compared with 1.1% a year in the 1990s.
• At least half of the next 10 years should be warmer than the previous record in 1998.
• Glaciers and sea ice have melted since 2000 at twice the rate of the 1980s and ‘90s.
• Greenland ice in 2007 thawed 60% above the record melt in 1998.
• An ice-free September in the Arctic Ocean could come in 2030, not 2100 as earlier predicted.
• West Antarctica ice loss increased 60% from 1996-2006 and the Antarctic Peninsula thaw was up 140% the same decade. Closing of the ozone hole over Antarctic will likely accelerate warming there.
• Melting land ice and thermal expansion could raise sea levels 6 feet by century’s end, rather than the earlier predicted 1.5 feet.
• Marine ecosystems will turn over 60% by 2050 because of extinctions and invasive species.

Impact on treaty talks
UN Secretary-General Ban Ki-Moon called the new report a “wake-up call” for countries meeting in Copenhagen in December to try to reach accord on a successor to the Kyoto Protocol.

"Shying away from a major agreement in Copenhagen will probably be unforgivable, if you look back ... at this moment,” said UNEP executive director Achim Steiner.

Countries still disagree about the amount of GHG emissions industrialized and developing countries should cut and how much rich countries should help fund poor ones for adaptation and low-carbon economic development. Some European countries pledging 20% or more in cuts (below 1990 levels) by 2020 criticize the U.S., which is responsible for the most existing atmospheric CO2, for doing too little. The House-passed climate bill targets a 17% reduction (from 2005 levels) by 2020 (that’s about 4% below 1990) and the Senate is thought to be looking at reducing that number. That’s pretty pathetic.

As UNEP report contributor Robert Correl put it: Emissions are accelerating. “We’re not going in the right direction.”

To download the report go to www.unep.org/compendium2009

(Sources: Dallas Morning News, Washington Post, UNEP.com, AP.)

Tuesday, May 06, 2008

Etc.: Arctic melt forecast, ocean ‘deserts,’ and ozone hole’s impact on climate change

(Image if the Arctic summer ice melt from Flickr and Image Editor.)

Arctic ice will shrink to a record level this year because it is thinner and younger than ever, according to a climate researcher at the University of Colorado. Last year saw a record melt as well. Over the past 10 years ice in the Arctic has shrunk about 10% as temperatures warmed. Arctic ice acts as an air conditioner for the rest of the world as air currents pass over it. See Reuters.

As the ozone hole over the Antarctic closes, ice there may begin to melt faster, scientists warn. For the past 3 decades the North and South poles have been polar opposites, as ice melted in the Arctic and increased in most of the Antarctic. But as ozone-harmful gases have been curtailed and the hole begins to close, we now face the likelihood of melting at the South Pole too, according to a study published in Eos. The hole has strengthened westerly winds, which cut the Antartic off from areas to the north that were warming. Only the northernmost peninsula has been warming. (ClimateWire)

Oxygen-deprived ocean “deserts” are spreading as waters warm and circulation patterns change, according to a study published last week in Science. The increase is consistent with what climate models forecast as a result of increased greenhouse gases. As water warms it holds less oxygen and these deserts in the tropical Atlantic and Pacific are unable to support most marine life. The deserts are different from the “dead zones” in rivers, mainly caused by fertilizer run-off. See latimes.com

Sunday, April 27, 2008

Photo Gallery: Things that won't be there anymore -- if we don't act quickly on global warming

Weekly angst: My husband has a video, "Things That Aren't There Anymore," about places he remembers from his youth in Pittsburgh -- like an ice cream shop, an amusement park and a shopping arcade. The grandkids -- Bryan, Evan and Sabrina -- laugh at the title and the concept. But they won't be laughing if they end up showing their own grandkids video of all the natural things from their youth that won't be there anymore, thanks to global warming and our unwillingness to stop it. Here are some of the things they may find only in captivity at a zoo, dead and stuffed in a museum or on a video -- if we don't get serious about greenhouse gases.