Dear EarthTalk: I’ve noticed a lot of beach erosion along the eastern U.S. coast. Beaches are virtually non-existent in places. Is this a usual cycle that will self-correct, or are these beaches permanently gone from sea level rise or other environmental causes? – Jan Jesse, Morristown, TN
Unfortunately for beach lovers and owners of high-priced beach-front homes, coastal erosion in any form is usually a one-way trip. Man-made techniques such as beach nourishment—whereby sand is dredged from offshore sources and deposited along otherwise vanishing beaches—may slow the process, but nothing short of global cooling or some other major geomorphic change will stop it altogether.
Beach Erosion Not Simply “Shifting Sands”
According to Stephen Leatherman (“Dr. Beach”) of the National Healthy Beaches Campaign, beach erosion is defined by the actual removal of sand from a beach to deeper water offshore or alongshore into inlets, tidal shoals and bays. Such erosion can result from any number of factors, including the simple inundation of the land by rising sea levels resulting from the melting of the polar ice caps.
Beach Erosion is an Ongoing Problem
Leatherman cites U.S. Environmental Protection Agency estimates that between 80 and 90 percent of the sandy beaches along America’s coastlines have been eroding for decades. In many of these cases, individual beaches may be losing only a few inches per year, but in some cases the problem is much worse. The outer coast of Louisiana, which Leatherman refers to as “the erosion ‘hot spot’ of the U.S.,” is losing some 50 feet of beach every year.
Is Global Warming Accelerating Beach Erosion?
Of particular concern is the effect climate change, which not only causes sea levels to rise but also increases the severity and possibly the frequency of harsh storms, has on beach erosion. “While sea level rise sets the conditions for landward displacement of the shore, coastal storms supply the energy to do the ‘geologic work’ by moving the sand off and along the beach,” writes Leatherman on his DrBeach.org website. “Therefore, beaches are greatly influenced by the frequency and magnitude of storms along a particular shoreline.”
What Can You Do Personally to Stop Beach Erosion? Not Much
Besides collectively lowering our greenhouse gas emissions substantially, there is little that individuals—let alone coastal landowners—can do to stop beach erosion. Building a bulkhead or seawall along one or a few coastal properties may protect homes from damaging storm waves for a few years, but could end up doing more harm than good. “Bulkheads and seawalls may accelerate beach erosion by reflecting wave energy off the facing wall, impacting adjacent property owners as well,” writes Leatherman, adding that such structures along retreating shorelines eventually cause diminished beach width and even loss.
Slowing or Stopping Beach Erosion is Possible, but Pricey
Other larger scale techniques like beach nourishment may have better track records, at least in terms of slowing or delaying beach erosion, but are expensive enough as to warrant massive taxpayer expenditures. In the early 1980s, the city of Miami spent some $65 million adding sand to a 10-mile stretch of fast-eroding shoreline. Not only did the effort stave off erosion, it helped revitalize the tony South Beach neighborhood and rescue hotels, restaurants and shops there that cater to the rich and famous.
GOT AN ENVIRONMENTAL QUESTION? Send it to: EarthTalk, c/o E/The Environmental Magazine, P.O. Box 5098, Westport, CT 06881; submit it at: www.emagazine.com/earthtalk/thisweek/, or e-mail: earthtalk@emagazine.com.
EarthTalk is a regular feature of E/The Environmental Magazine. Selected EarthTalk columns are reprinted on About Environmental Issues by permission of the editors of
Tuesday, April 20, 2010
Billions of People Face Food Shortages Due to Global Warming, Study Warns
Half of the world’s population could face severe food shortages by the end of this century as rising temperatures shorten the growing season in the tropics and subtropics, increase the risk of drought, and reduce the harvests of dietary staples such as rice and maize by 20 percent to 40 percent, according to a study published in the journal Science.
Global warming is expected to affect agriculture in every part of the world but it will have greater impact in the tropics and subtropics, where crops are less able to adapt to climate change and food shortages are already starting to occur due to rapid population growth.
Scientists at Stanford University and the University of Washington, who worked on the study, discovered that by 2100 there is a 90 percent chance that the coolest temperatures in the tropics during the growing season will be higher than the hottest temperatures recorded in those regions through 2006. Even more temperate parts of the world can expect to see previously record-high temperatures become the norm.
With the world population expected to double by the end of the century, the need for food will become increasingly urgent as rising temperatures force nations to retool their approach to agriculture, create new climate-resistant crops, and develop additional strategies to ensure an adequate food supply for their people.
All of that could take decades, according to Rosamond Naylor, who is director of food security and the environment at Stanford. Meanwhile, people will have fewer and fewer places to turn for food when their local supplies begin to run dry.
"When all the signs point in the same direction, and in this case it's a bad direction, you pretty much know what's going to happen," said David Battisti, the University of Washington scientist who led the study. "You're talking about hundreds of millions of additional people looking for food because they won't be able to find it where they find it now.
Global warming is expected to affect agriculture in every part of the world but it will have greater impact in the tropics and subtropics, where crops are less able to adapt to climate change and food shortages are already starting to occur due to rapid population growth.
Scientists at Stanford University and the University of Washington, who worked on the study, discovered that by 2100 there is a 90 percent chance that the coolest temperatures in the tropics during the growing season will be higher than the hottest temperatures recorded in those regions through 2006. Even more temperate parts of the world can expect to see previously record-high temperatures become the norm.
With the world population expected to double by the end of the century, the need for food will become increasingly urgent as rising temperatures force nations to retool their approach to agriculture, create new climate-resistant crops, and develop additional strategies to ensure an adequate food supply for their people.
All of that could take decades, according to Rosamond Naylor, who is director of food security and the environment at Stanford. Meanwhile, people will have fewer and fewer places to turn for food when their local supplies begin to run dry.
"When all the signs point in the same direction, and in this case it's a bad direction, you pretty much know what's going to happen," said David Battisti, the University of Washington scientist who led the study. "You're talking about hundreds of millions of additional people looking for food because they won't be able to find it where they find it now.
Readers Respond: What are you doing to help reduce global warming
Reducing global warming may require global solutions, but it also requires personal action by millions of individuals. What are you doing in your own life to help reduce global warming, and which of those strategies would you recommend to others? Share Your Ideas
Number of animals raised per year
Those who argue against the veg diet to stop global warming have some serious misunderstandings. Worldwide 60 billion (yes, 60 BILLION) animals are killed every year for meat. Those 60 billion animals create a far bigger burden than 6 billion humans. They create 130 times more excrement (which is untreated and poured into our waterways or buried where it pollutes underground water sources), over 50% of greenhouse gases, causes the majority of deforestation in the Amazon, and a whole host of other environmental problems (thousands of miles of poisoned rivers, 400 dead zones in our oceans, uses 70% of all usable water, over 60% of grain, etc). These animals do not happen naturally - they are raised in artificial numbers that would never happen in nature. They are an enormous burden on our planet and its people (while 10000 children die each day of starvation, we feed over 60% of the world's grain to animals. That grain would feed billions more people) Go veg, be green!
—Guest Vegg Mom
Most important thing left off list!
The meat industry is responsible for more greenhouse gas emissions than all forms of transportation combined! The Worldwatch Institute recently released a study indicating that the meat industry is repsonsible for 51% (!) of greenhouse gases. Cut your meat consumption to save the planet. Go Veg, Be Green to save our planet!
—Guest Debra
Small steps add up
Reduce, reuse, recycle are the tenets we live by. We: 1. eliminated bottled water; now use reusable stainless steel bottles & own water 2. use CFLs 3. grow many of our own veggies 4. shop local - farmers markets & locally grown meats & eggs 5. Barter for use of items we don't use often 6. Use freecycle/donate to charity to give others an opportunity to use items we no longer need 7. Hang our clothes outside on a clothesline to dry 8. Use reusable shopping bags everywhere we shop 9. Carpool to work with 2 others 10. Replaced our water heater; turned down the temp 11. Replaced our furnace; use a programmable thermostat 12. Replaced our home's windows 13. Planted multi-purpose landscape beds with ornamentals as well as small fruits (e.g, blueberries, strawberries, currants, rhubarb) and room for veggies 14. Use blinds to cut heat loss in winter/heat gain in summer 15. Turn off the lights, PC, TV, etc 16. Taught our kids to be environmentally conscious!
—Guest Green one
Global warming
Use public transport instead of using private vehicles.
—Guest Sandy
Getting Involved
Get involved in a community activity (one that educates others about reducing energy or doing Green Habitat For Humanity or Green the Ghetto-type projects) will not only get you out of the house and not using power while there, but you'll bring yourself closer to your community and create a sense of cooperative involvement; "we're all in this together" or "I am my brother's keeper". Perhaps most important, you'll feel better about yourself as will the people you help who in turn can be persuaded to serve their community in the same way.
—Guest Andy
Advocacy
SETTING UP AN ADVOCACY TO EDUCATE AND INFORM MY COMMUNITY PROTECT AND CONSERVE THE ENVIRONMENT.PPL.ATTITUDE HAVE TO CHANGE. Setting up an advocacy to educate and inform my community, protect and conserve the environment. People's attitudes have to change.
—Guest omang dave
zizi
I'll plant trees and encourage other to do so. It's so relaxing, enjoying fresh air under a bit tree you planted. It's more refreshing than an air-conditioned house and you'll be saving the environment too.
—Guest zizi
Save Mother Earth
We all should make resolution on this new year to plant at least 5 plants, save electricity, walk instead of using vehicles--it will make us healthy too. Make others aware of Global Warming. We also should discuss this in our offices and work places so that more and more people will join the mission to save Mother Earth. It is our duty to save earth because in this way we will gift a safe, beautiful and clean place to live in to our next generation. It is very important and urgent issue.
—Guest Rahul
Opinion
The best change is to try and teach our next generation of kids to be environmentally friendly and energy efficient. We have to stop all forms of mainstream utilization of fossil fuels. And to most who believe their one small appliance doesn't do much damage, they are wrong. You are a contributing factor that is capable of producing several tons of Carbon Dioxide every year, how much you expel depends on your lifestyle. The problem is the Earth has reached it's carrying capacity for the human population. We are slowly taking over and have already impacted EVERY piece of wildlife known to man, either directly or indirectly through pollution, farming, Logging, habitat fragmentation, construction, and hunting/poaching. We just all need to play our part to help the right people (who have the power to change things) understand the value and ecological importance of the factors nature contributes to us.
—Guest Freeman
global warming
I switch off all the lights whenever I am not at home.
—Guest taj
Terrace farming
When hills/mountains are not in use,a round curvy slope should be formed & plants should be grown there.
—Guest honey
reduce
we should less used electrical things that can give affect to atmosphere layer
—nur79
save electricity
I always switch off the electric appliance which are not being used. Eg., not leaving the TV on stand-by mode.
—Guest kanika
Global Warmings
1.Started Gardening 2.Bathing in cold water rather than using warm water 3.Switching of the PC and Lights when not in Use 4.Avoided using Plastic Bags and Plastic materials 5.Replaced CFL Bulbs with Normal Tube lights
—Guest Shanmuga Kumar
heat your house
you can use geo-thermal energy to heat your house rather than use oil, which releases harmful gases in the environment.
—Guest rinku
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What are you doing to help reduce global warming?
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All About Global Warming Global Warming and Much More!
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Conference & Exhibition on Biomass for Energy, 25-27 May 2010
www.elmia.se/en/worldbioenergy
Carbon dioxide equipment
Super-fine alcohol, DDGS equipment Carbon dioxide technology
www.keyualcohol.com
Number of animals raised per year
Those who argue against the veg diet to stop global warming have some serious misunderstandings. Worldwide 60 billion (yes, 60 BILLION) animals are killed every year for meat. Those 60 billion animals create a far bigger burden than 6 billion humans. They create 130 times more excrement (which is untreated and poured into our waterways or buried where it pollutes underground water sources), over 50% of greenhouse gases, causes the majority of deforestation in the Amazon, and a whole host of other environmental problems (thousands of miles of poisoned rivers, 400 dead zones in our oceans, uses 70% of all usable water, over 60% of grain, etc). These animals do not happen naturally - they are raised in artificial numbers that would never happen in nature. They are an enormous burden on our planet and its people (while 10000 children die each day of starvation, we feed over 60% of the world's grain to animals. That grain would feed billions more people) Go veg, be green!
—Guest Vegg Mom
Most important thing left off list!
The meat industry is responsible for more greenhouse gas emissions than all forms of transportation combined! The Worldwatch Institute recently released a study indicating that the meat industry is repsonsible for 51% (!) of greenhouse gases. Cut your meat consumption to save the planet. Go Veg, Be Green to save our planet!
—Guest Debra
Small steps add up
Reduce, reuse, recycle are the tenets we live by. We: 1. eliminated bottled water; now use reusable stainless steel bottles & own water 2. use CFLs 3. grow many of our own veggies 4. shop local - farmers markets & locally grown meats & eggs 5. Barter for use of items we don't use often 6. Use freecycle/donate to charity to give others an opportunity to use items we no longer need 7. Hang our clothes outside on a clothesline to dry 8. Use reusable shopping bags everywhere we shop 9. Carpool to work with 2 others 10. Replaced our water heater; turned down the temp 11. Replaced our furnace; use a programmable thermostat 12. Replaced our home's windows 13. Planted multi-purpose landscape beds with ornamentals as well as small fruits (e.g, blueberries, strawberries, currants, rhubarb) and room for veggies 14. Use blinds to cut heat loss in winter/heat gain in summer 15. Turn off the lights, PC, TV, etc 16. Taught our kids to be environmentally conscious!
—Guest Green one
Global warming
Use public transport instead of using private vehicles.
—Guest Sandy
Getting Involved
Get involved in a community activity (one that educates others about reducing energy or doing Green Habitat For Humanity or Green the Ghetto-type projects) will not only get you out of the house and not using power while there, but you'll bring yourself closer to your community and create a sense of cooperative involvement; "we're all in this together" or "I am my brother's keeper". Perhaps most important, you'll feel better about yourself as will the people you help who in turn can be persuaded to serve their community in the same way.
—Guest Andy
Advocacy
SETTING UP AN ADVOCACY TO EDUCATE AND INFORM MY COMMUNITY PROTECT AND CONSERVE THE ENVIRONMENT.PPL.ATTITUDE HAVE TO CHANGE. Setting up an advocacy to educate and inform my community, protect and conserve the environment. People's attitudes have to change.
—Guest omang dave
zizi
I'll plant trees and encourage other to do so. It's so relaxing, enjoying fresh air under a bit tree you planted. It's more refreshing than an air-conditioned house and you'll be saving the environment too.
—Guest zizi
Save Mother Earth
We all should make resolution on this new year to plant at least 5 plants, save electricity, walk instead of using vehicles--it will make us healthy too. Make others aware of Global Warming. We also should discuss this in our offices and work places so that more and more people will join the mission to save Mother Earth. It is our duty to save earth because in this way we will gift a safe, beautiful and clean place to live in to our next generation. It is very important and urgent issue.
—Guest Rahul
Opinion
The best change is to try and teach our next generation of kids to be environmentally friendly and energy efficient. We have to stop all forms of mainstream utilization of fossil fuels. And to most who believe their one small appliance doesn't do much damage, they are wrong. You are a contributing factor that is capable of producing several tons of Carbon Dioxide every year, how much you expel depends on your lifestyle. The problem is the Earth has reached it's carrying capacity for the human population. We are slowly taking over and have already impacted EVERY piece of wildlife known to man, either directly or indirectly through pollution, farming, Logging, habitat fragmentation, construction, and hunting/poaching. We just all need to play our part to help the right people (who have the power to change things) understand the value and ecological importance of the factors nature contributes to us.
—Guest Freeman
global warming
I switch off all the lights whenever I am not at home.
—Guest taj
Terrace farming
When hills/mountains are not in use,a round curvy slope should be formed & plants should be grown there.
—Guest honey
reduce
we should less used electrical things that can give affect to atmosphere layer
—nur79
save electricity
I always switch off the electric appliance which are not being used. Eg., not leaving the TV on stand-by mode.
—Guest kanika
Global Warmings
1.Started Gardening 2.Bathing in cold water rather than using warm water 3.Switching of the PC and Lights when not in Use 4.Avoided using Plastic Bags and Plastic materials 5.Replaced CFL Bulbs with Normal Tube lights
—Guest Shanmuga Kumar
heat your house
you can use geo-thermal energy to heat your house rather than use oil, which releases harmful gases in the environment.
—Guest rinku
1-15 of 61Next
Share Your Ideas
What are you doing to help reduce global warming?
Guest Name*Login with Membername or Register
Response TitleResponse50-character minimum
1000-character limit
(optional)
Receive a one-time notification when your response is published.
User AgreementRelated Articles
Reduce Global Warming - What are You Doing to Help Reduce Global Warming?
Reduce Global Warming - What are You Doing to Help Reduce Global Warming?
Effects of Global Warming and Future Outlook of Global Warming
Sima
Neapolitan Meat Ragù - Carne al Ragù
Larry West
Environmental Issues Guide
Sign up for my Newsletter
My BlogMy Forum
Sponsored Links
Stop Polluting Oceans
Start acting today before it gets too late. Support Greenpeace now!
SaveYourSeas.org
Degree in Solar Energy.
Amity’s UGC Recognized Degree Top faculty, Great placement
www.Amity.Edu/Admission
Carbon Management Courses
Online Training for Beginners and Advanced. Become a GHG Expert
www.ghginstitute.org
Global Warming
All About Global Warming Global Warming and Much More!
Peeplo.com/Top_Results
World Bioenergy 2010
Conference & Exhibition on Biomass for Energy, 25-27 May 2010
www.elmia.se/en/worldbioenergy
Carbon dioxide equipment
Super-fine alcohol, DDGS equipment Carbon dioxide technology
www.keyualcohol.com
Tuesday, April 6, 2010
Arctic Sea Ice News And Anylsis
Cold snap causes late-season growth spurt
Arctic sea ice reached its maximum extent for the year on March 31 at 15.25 million square kilometers (5.89 million square miles). This was the latest date for the maximum Arctic sea ice extent since the start of the satellite record in 1979.
Early in March, Arctic sea ice appeared to reach a maximum extent. However, after a short decline, the ice continued to grow. By the end of March, total extent approached 1979 to 2000 average levels for this time of year. The late-season growth was driven mainly by cold weather and winds from the north over the Bering and Barents Seas. Meanwhile, temperatures over the central Arctic Ocean remained above normal and the winter ice cover remained young and thin compared to earlier years.
Figure 1. Arctic sea ice extent for March 2010 was 15.10 million square kilometers (5.83 million square miles). The magenta line shows the 1979 to 2000 median extent for that month. The black cross indicates the geographic North Pole. Sea Ice Index data. About the data.
—Credit: National Snow and Ice Data Center
High-resolution image Overview of conditions
Arctic sea ice extent averaged for March 2010 was 15.10 million square kilometers (5.83 million square miles). This was 650,000 square kilometers (250,000 square miles) below the 1979 to 2000 average for March, but 670,000 square kilometers (260,000 square miles) above the record low for the month, which occurred in March 2006.
Ice extent was above normal in the Bering Sea and Baltic Sea, but remained below normal over much of the Atlantic sector of the Arctic, including the Baffin Bay, and the Canadian Maritime Provinces seaboard. Extent in other regions was near average.
Figure 2. The graph above shows daily sea ice extent as of April 4, 2010. The solid light blue line indicates 2010; green shows 2007; dark blue indicates 1999, the year with the previous latest maximum extent, which occurred on March 29, 1999; and solid gray indicates average extent from 1979 to 2000. The gray area around the average line shows the two standard deviation range of the data. Sea Ice Index data.
—Credit: National Snow and Ice Data Center
High-resolution image
Conditions in context
Sea ice reached its maximum extent for the year on March 31, the latest maximum date in the satellite record. The previous latest date was on March 29, 1999. The maximum extent was 15.25 million square kilometers (5.89 million square miles). This was 670,000 square kilometers (260,000 square miles) above the record low maximum extent, which occurred in 2006.
Sea ice extent seemed to reach a maximum during the early part of the month, but after a brief decline, ice extent increased slowly and steadily through the end of the month. By the end of the month, extent had approached the 1979 to 2000 average. During March 2010, ice extent grew at an average of 13,200 square kilometers (5100 square miles) per day. Usually there is a net loss of ice through the month.
Figure 3. Monthly March ice extent for 1979 to 2010 shows a decline of 2.6% per decade.
—Credit: National Snow and Ice Data Center
High-resolution image March 2010 compared to past years
The average ice extent for March 2010 was 670,000 square kilometers (260,000 square miles) higher than the record low for March, observed in 2006. The linear rate of decline for March over the 1978 to 2010 period is 2.6% per decade.
Figure 4. The map of sea level pressure (in millibars) for March 2010 shows high pressure over the central Arctic (areas in yellow and orange) and areas of low pressure over the Bering and Barents seas (areas in blue and purple). The low pressure systems over the Bering and Barents seas have helped to push the ice edge southward.
—Credit: National Snow and Ice Data Center courtesy NOAA/ESRL Physical Sciences Division
High-resolution image Late-season growth spurt
The maximum Arctic sea ice extent may occur as early as mid-February to as late as the last week of March. As sea ice extent approaches the seasonal maximum, extent can vary quite a bit from day to day because the thin, new ice at the edge of the pack is sensitive to local wind and temperature patterns. This March, low atmospheric pressure systems persisted over the Gulf of Alaska and north of Scandinavia. These pressure patterns led to unusually cold conditions and persistent northerly winds in the Bering and Barents Seas, which pushed the ice edge southward in these two regions.
Figure 5. This map of air temperature anomalies for March 2010, at the 925 millibar level (roughly 1,000 meters or 3,000 feet above the surface), shows warmer than usual temperatures over most of the Arctic Ocean, but colder than usual temperatures in the Bering and Barents seas, where sea ice extent is above normal. Areas in orange and red correspond to positive (warm) anomalies. Areas in blue and purple correspond to negative (cool) anomalies.
—Credit: National Snow and Ice Data Center courtesy NOAA/ESRL Physical Sciences Division
High-resolution imageMeanwhile, elsewhere in the Arctic
This winter's strong negative mode of the Arctic Oscillation was moderated through the month of March. Average air temperatures for the month nevertheless remained above average over the Arctic Ocean region. Overall for the winter, temperatures over most of the Arctic were above average, while northern Europe and Siberia were colder than usual.
Figure 6. These images show the change in ice age from fall 2009 to spring 2010. The negative Arctic Oscillation this winter slowed the export of older ice out of the Arctic. As a result, the percentage of ice older than two years was greater at the end of March 2010 than over the past few years.
—Credit: National Snow and Ice Data Center courtesy J. Maslanik and C. Fowler, CU Boulder
High-resolution imageIce age and thickness
The late date of the maximum extent, though of special interest this year, is unlikely to have an impact on summer ice extent. The ice that formed late in the season is thin, and will melt quickly when temperatures rise.
Scientists often use ice age data as a way to infer ice thickness—one of the most important factors influencing end-of-summer ice extent. Although the Arctic has much less thick, multiyear ice than it did during the 1980s and 1990s, this winter has seen some replenishment: the Arctic lost less ice the past two summers compared to 2007, and the strong negative Arctic Oscillation this winter prevented as much ice from moving out of the Arctic. The larger amount of multiyear ice could help more ice to survive the summer melt season. However, this replenishment consists primarily of younger, two- to three-year-old multiyear ice; the oldest, and thickest multiyear ice has continued to decline. Although thickness plays an important role in ice melt, summer ice conditions will also depend strongly on weather patterns through the melt season.
At the moment there are no Arctic-wide satellite measurements of ice thickness, because of the end of the NASA Ice, Cloud, and Land Elevation Satellite (ICESat) mission last October. NASA has mounted an airborne sensor campaign called IceBridge to fill this observational gap.
Arctic sea ice reached its maximum extent for the year on March 31 at 15.25 million square kilometers (5.89 million square miles). This was the latest date for the maximum Arctic sea ice extent since the start of the satellite record in 1979.
Early in March, Arctic sea ice appeared to reach a maximum extent. However, after a short decline, the ice continued to grow. By the end of March, total extent approached 1979 to 2000 average levels for this time of year. The late-season growth was driven mainly by cold weather and winds from the north over the Bering and Barents Seas. Meanwhile, temperatures over the central Arctic Ocean remained above normal and the winter ice cover remained young and thin compared to earlier years.
Figure 1. Arctic sea ice extent for March 2010 was 15.10 million square kilometers (5.83 million square miles). The magenta line shows the 1979 to 2000 median extent for that month. The black cross indicates the geographic North Pole. Sea Ice Index data. About the data.
—Credit: National Snow and Ice Data Center
High-resolution image Overview of conditions
Arctic sea ice extent averaged for March 2010 was 15.10 million square kilometers (5.83 million square miles). This was 650,000 square kilometers (250,000 square miles) below the 1979 to 2000 average for March, but 670,000 square kilometers (260,000 square miles) above the record low for the month, which occurred in March 2006.
Ice extent was above normal in the Bering Sea and Baltic Sea, but remained below normal over much of the Atlantic sector of the Arctic, including the Baffin Bay, and the Canadian Maritime Provinces seaboard. Extent in other regions was near average.
Figure 2. The graph above shows daily sea ice extent as of April 4, 2010. The solid light blue line indicates 2010; green shows 2007; dark blue indicates 1999, the year with the previous latest maximum extent, which occurred on March 29, 1999; and solid gray indicates average extent from 1979 to 2000. The gray area around the average line shows the two standard deviation range of the data. Sea Ice Index data.
—Credit: National Snow and Ice Data Center
High-resolution image
Conditions in context
Sea ice reached its maximum extent for the year on March 31, the latest maximum date in the satellite record. The previous latest date was on March 29, 1999. The maximum extent was 15.25 million square kilometers (5.89 million square miles). This was 670,000 square kilometers (260,000 square miles) above the record low maximum extent, which occurred in 2006.
Sea ice extent seemed to reach a maximum during the early part of the month, but after a brief decline, ice extent increased slowly and steadily through the end of the month. By the end of the month, extent had approached the 1979 to 2000 average. During March 2010, ice extent grew at an average of 13,200 square kilometers (5100 square miles) per day. Usually there is a net loss of ice through the month.
Figure 3. Monthly March ice extent for 1979 to 2010 shows a decline of 2.6% per decade.
—Credit: National Snow and Ice Data Center
High-resolution image March 2010 compared to past years
The average ice extent for March 2010 was 670,000 square kilometers (260,000 square miles) higher than the record low for March, observed in 2006. The linear rate of decline for March over the 1978 to 2010 period is 2.6% per decade.
Figure 4. The map of sea level pressure (in millibars) for March 2010 shows high pressure over the central Arctic (areas in yellow and orange) and areas of low pressure over the Bering and Barents seas (areas in blue and purple). The low pressure systems over the Bering and Barents seas have helped to push the ice edge southward.
—Credit: National Snow and Ice Data Center courtesy NOAA/ESRL Physical Sciences Division
High-resolution image Late-season growth spurt
The maximum Arctic sea ice extent may occur as early as mid-February to as late as the last week of March. As sea ice extent approaches the seasonal maximum, extent can vary quite a bit from day to day because the thin, new ice at the edge of the pack is sensitive to local wind and temperature patterns. This March, low atmospheric pressure systems persisted over the Gulf of Alaska and north of Scandinavia. These pressure patterns led to unusually cold conditions and persistent northerly winds in the Bering and Barents Seas, which pushed the ice edge southward in these two regions.
Figure 5. This map of air temperature anomalies for March 2010, at the 925 millibar level (roughly 1,000 meters or 3,000 feet above the surface), shows warmer than usual temperatures over most of the Arctic Ocean, but colder than usual temperatures in the Bering and Barents seas, where sea ice extent is above normal. Areas in orange and red correspond to positive (warm) anomalies. Areas in blue and purple correspond to negative (cool) anomalies.
—Credit: National Snow and Ice Data Center courtesy NOAA/ESRL Physical Sciences Division
High-resolution imageMeanwhile, elsewhere in the Arctic
This winter's strong negative mode of the Arctic Oscillation was moderated through the month of March. Average air temperatures for the month nevertheless remained above average over the Arctic Ocean region. Overall for the winter, temperatures over most of the Arctic were above average, while northern Europe and Siberia were colder than usual.
Figure 6. These images show the change in ice age from fall 2009 to spring 2010. The negative Arctic Oscillation this winter slowed the export of older ice out of the Arctic. As a result, the percentage of ice older than two years was greater at the end of March 2010 than over the past few years.
—Credit: National Snow and Ice Data Center courtesy J. Maslanik and C. Fowler, CU Boulder
High-resolution imageIce age and thickness
The late date of the maximum extent, though of special interest this year, is unlikely to have an impact on summer ice extent. The ice that formed late in the season is thin, and will melt quickly when temperatures rise.
Scientists often use ice age data as a way to infer ice thickness—one of the most important factors influencing end-of-summer ice extent. Although the Arctic has much less thick, multiyear ice than it did during the 1980s and 1990s, this winter has seen some replenishment: the Arctic lost less ice the past two summers compared to 2007, and the strong negative Arctic Oscillation this winter prevented as much ice from moving out of the Arctic. The larger amount of multiyear ice could help more ice to survive the summer melt season. However, this replenishment consists primarily of younger, two- to three-year-old multiyear ice; the oldest, and thickest multiyear ice has continued to decline. Although thickness plays an important role in ice melt, summer ice conditions will also depend strongly on weather patterns through the melt season.
At the moment there are no Arctic-wide satellite measurements of ice thickness, because of the end of the NASA Ice, Cloud, and Land Elevation Satellite (ICESat) mission last October. NASA has mounted an airborne sensor campaign called IceBridge to fill this observational gap.
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