Stories tagged global warming

Glaciers in the North American Rockies are changing in response to rising global temperatures and other variables. Free presentation at Macalester College by Professor Kelly MacGregor 7:00 pm, Thursday, 10/26/2006 in Weyerhaeuser Memorial Chapel.

Oct
15
2006

Coral in trouble: photo from NOAA via Wikimedia
Coral in trouble: photo from NOAA via Wikimedia

Oceans appear unhealthy

What if Earth's oceans get so sick they start a chain reaction of death? Zones of death are showing up in the Gulf and off the coast of Oregon. The coral reefs off Madagascar, Australia, and Belize are dying.

More than 90 percent of the earth’s living biomass (weight of living matter) is found in the oceans, and 90 percent of that is made up of single cell and microbial species. ...
There are signs that marine life is failing right at the bottom of the food web as the result of global warming, which could start a series of aggravating feedback effects on climate change. Institute of Science in Society

"Increasing carbon dioxide in the atmosphere has had effects in the ocean, where it's causing increased acidity," says director of NSF's biological oceanography program, Phil Taylor, "This increasing acidity has the potential to disrupt the calcifying processes that lead to coral reef development, for example, as well as disrupt those same processes in the microscopic plankton that form the center of the ocean's food web." National Science Foundation

Cacium carbonate depends upon non-acidic ocean

Since the industrial revolution began, ocean pH has dropped by approximately 0.1 units, and it is estimated that it will drop by a further 0.3 - 0.4 units by 2100 as the ocean absorbs more anthropogenic CO2 (Caldeira and Wickett, 2003; Orr et al., 2005) (via Wikipedia). Ocean life which use calcium carbonate find themselves dissolving when their environment is too acidic.

More research needed

In a recent study, scientists discovered several small reefs near Madagascar with corals that appeared to be resilient to rising sea temperatures. These resilient areas could be used to reseed damaged reefs ensuring the continued existence of coral reefs around the world and the marine species that rely upon them for survival.

Coral bleaching should serve as a red flag warning us that we need to understand the complex interactions between changing ocean chemistry and marine ecology. We need to develop research strategies to better understand the long-term vulnerabilities of sensitive marine organisms to these changes.

A new study found a link between human use of fossil fuels and an increase in the severity of hurricanes. The burning of fossil fuels has increased the level of greenhouse gases in the atmosphere, which has led to the warming of oceans in regions where hurricanes develop. The warmer the ocean water, the more severe the hurricane.

Sep
10
2006

Permafrost polygons: Permafrost is rapidly melting away, releasing methane, and carbon dioxide into the Earth's atmosphere.  Photo courtesy of the U.S. Geological Survey.
Permafrost polygons: Permafrost is rapidly melting away, releasing methane, and carbon dioxide into the Earth's atmosphere. Photo courtesy of the U.S. Geological Survey.

Greenhouse gases that have been trapped in frozen permafrost are being released from the melting soil much faster than was previously thought. The most notable one of these gases is methane, which is being released into the atmosphere at a rate 5 times greater than was previously thought.

Methane is an effective heat trapping agent, it is 23 times more powerful at trapping heat in the atmosphere than carbon dioxide. It is practically harmless when it is frozen in permafrost.

Permafrost is ground that has consistently been at a temperature of zero degrees Celsius (32 degrees Fahrenheit) for two or more years. Permafrost occurs in regions of Arctic climates, such as the tundra of Alaska, northern Canada, and Siberia. Unfortunately, when these frozen climates get too warm, the trapped atmospheric gases are released. Unfortunately, this is now happening too frequently due to global warming.

The release of methane from melting permafrost speeds up the global warming process. The current warming of the earth causes the permafrost to melt, which causes methane and carbon dioxide to be released into the atmosphere, which causes more warming. It’s a horrible cycle and scientists are worried that it will eventually go out of control, setting off a “climate time bomb.”

Scientists are unsure whether or not methane or carbon dioxide is the worst greenhouse gas. While methane traps more heat, it only lingers in the atmosphere for around 10 years. Carbon dioxide traps less heat, but it typically remains in the atmosphere for a century. Neither of these gases is good.

Sounds like quite the problem. What do you think we can do about it?

Sep
07
2006

Farming the Wind: photo by Dirk Ingo Franke.   licensed under Creative Commons Attribution ShareAlike 1.0
Farming the Wind: photo by Dirk Ingo Franke. licensed under Creative Commons Attribution ShareAlike 1.0

Want to make a difference?

Did you know that you can insist that the amount of electricity you use be produced without generating carbon dioxide emissions or other forms of pollution (mercury, sulfer). Windsource electricity is produced without air emissions, such as carbon dioxide and sulfur dioxide, both considered to contribute to greenhouse gases. Wind-generated electricity also uses no water and therefore requires no water treatment during production. I am doing this by joining the Windsource program.

Xcel Energy will be held accountable for using Windsource funds appropriately: it must file annual reports with the Minnesota Department of Commerce and Minnesota Public Utilities Commission, accounting for program revenues and expenses and wind generation and sales. In addition, all wind facilities supplying the Windsource program will be certified by the Minnesota Department of Commerce. Sierraclub

What does it cost?

I have agreed to pay $2 per 100 kWh extra on my electric bill. This month I used 304 kWh so I was billed an extra $6.08. Since my electricity is pollution free I was rebated the Fuel Cost Adjustment that I otherwise would have paid ($2.76). So I paid an extra $3.32 last month know that I am helping rather than hurting our future environment. When fuel cost rise enough the rebate can become greater than what you pay for Windsource. You can sign up for Windsource here or call 1-800-895-4999 anytime.

Sep
03
2006

California's 25/20 vision: photo from Wikimedia
California's 25/20 vision: photo from Wikimedia

A 25 percent reduction in greenhouse gas emissions by 2020

California seeks to again lead the world toward a better future. After last weeks "one million solar roofs" legislation, this week California politicians are working out details that will reduce their green house emissions 25 per cent by the year 2020.

The legislation will require all businesses, from automakers to cement manufacturers, to reduce emissions beginning as early as 2012 to meet the 2020 cap. The state's 11-member Air Resources Board, which is appointed by the governor, will be charged with developing targets for each industry and for seeing that those targets are met. The board now will embark on a years-long process to fully develop regulations. The board could impose fees on some industries to pay for new programs that could do everything from requiring truckers to use biodiesel fuels to forcing farmers to handle animal waste differently.San Francisco Chronicle

California is the world's 12th-largest emitter of greenhouse gases, responsible for 10 percent of the carbon dioxide produced nationally and 2.5 percent globally. Global scientists agree that to prevent catastrophic temperature increases in this century, greenhouse gas emissions by 2050 would have to be 70 to 80 percent lower than 1990 levels.

Cap emissions; buy and sell emissions credits

Last week Sen. Dianne Feinstein, the state's senior Democratic legislator, pledged at the Commonwealth Club to introduce legislation in January that would place mandatory caps on industrial emissions. She also supports a federal cap-and-trade bill, a market-based approach for lowering emissions.(see Buzz Blog post about buying and selling pollution) For example, it would allow farmers and landowners who plant trees or convert crops into bio-fuels to earn emission credits that could be sold to companies that exceed emission limits.

What will it cost and who will pay

Some predict that because "green" energy is more expensive, many companies will move out of California. Others insist that investment capital and "clean-tech" jobs will result, similar to when California led the way with Silicon Valley. California would become more efficient and self reliant. This could give them a head start in a future that will certainly need to do something about global warming and rising energy costs.

Jul
29
2006

Amazon Rainforest: Rainforest could become desert.   photo from NASA
Amazon Rainforest: Rainforest could become desert. photo from NASA

Amazon rainforest could become a desert

And that could speed up global warming with 'incalculable consequences', says alarming new research. Studies by the blue-chip Woods Hole Research Centre, carried out in Amazonia, have concluded that the forest cannot withstand more than two consecutive years of drought without breaking down. And that process, which would be irreversible, could begin as early as next year.

The Amazon rainforest is huge

For those who'd like some perspective, the Amazon rainforest represents half the rainforests in the world. It encompasses 1.2 billion acres, or 1.875 million square miles. That's 3.25% of the planets land mass. That’s a huge chunk of land. So if this report is accurate, it’s far from being insignificant.
The Amazon now appears to be entering its second successive year of drought, raising the possibility that it could start dying next year. The immense forest contains 90 billion tons of carbon, enough in itself to increase the rate of global warming by 50 per cent.
Read more from The Independent (U.K.), July 23, 2006

Jul
28
2006

Scientists are studying a 70-mile "dead zone" off the coast of Oregon.

First noticed in 2002, the dead zone is larger this year than in previous years.

What is a dead zone? It's an large area of water that's very low in oxygen and can't support life. (Scientists call this "hypoxia.") Dead zones are caused by the explosive growth of tiny aquatic plants called phytoplankton. When the phytoplankton die, they are decomposed by bacteria. Massive numbers of bacteria use up the oxygen in the water. Any animals that can swim out of the low-oxygen water--like many fish--do so. Others--some fish, many crabs, and others--suffocate because they can't get enough oxygen to live.

Dead crabs: Dead Dungeness crabs on beach, Oregon Coast (Photo by Jane Lubchenco)
Dead crabs: Dead Dungeness crabs on beach, Oregon Coast (Photo by Jane Lubchenco)

In this case, the phytoplankton blooms are caused when north winds cause upwelling in the water column. The cooler water is rich in nutrients, providing a feast for the phytoplankton. When the wind dies down, the upwelling stops, and many phytoplankton die a natural death. Their decomposition results in water that is deadly because it lacks oxygen needed for life.

This year, the upwelling started in April, stopped in May, and started up again in June. The off-and-on upwelling creates a thick mat of organic material that rots and uses up the oxygen in the water. Then, when a new upwelling occurs, the oxygen-depleted water moves toward shore, killing the plants and animals that can't get out of its way.

Measuring oxygen levels: Chris Holmes (left) and Dr. Francis Chan (right), PISCO researchers measuring oxygen levels off the Oregon coast from the OSU research vessel Elakha (Photo by Jane Lubchenco)
Measuring oxygen levels: Chris Holmes (left) and Dr. Francis Chan (right), PISCO researchers measuring oxygen levels off the Oregon coast from the OSU research vessel Elakha (Photo by Jane Lubchenco)

So, why the upwelling? Jane Lubchenco, professor of marine ecology at Oregon State University and a member of the Pew Oceans Commission, told the Associated Press:

"We are seeing wild swings from year to year in the timing and duration of the winds that are favorable for upwelling. ... This increased variability in the winds is consistent with what we would expect under climate change."

Global warming is also the suspect in dead zones off Namibia, South Africa, and Peru.

(The dead zone in the Gulf of Mexico at the mouth of the Mississippi River is caused by agricultural runoff containing fertilizers. The river carries all those nutrients into the Gulf, creating algal blooms that use up all the oxygen.)

Jul
06
2006

Antarctic Peninsula Glacier: Courtesy of Wikipedia Images
Antarctic Peninsula Glacier: Courtesy of Wikipedia Images

More and more people are getting the amazing opportunity to visit Antarctica. It is predicted that at least 28,000 tourists will travel to this frigid continent during the 2006-2007 tourist season. In addition, close to 10,000 scientists will likely visit. As the number of researchers and tourists traveling to Antarctica increases, so may the number of invasive species that are making their way there.

An invasive species is a plant or animal species that was brought intentionally or accidentally into a new ecosystem and has developed the ability to reproduce in its new habitat. These species can takeover the native species in their new environment.

What are some of the invasive species arriving in Antarctica?

  • Annual bluegrass, a type of grass ideal for putting greens, recently arrived on King George Island, an island off the coast of Antarctica. It is likely that this grass originally came to the island with a human visitor.
  • Northern Atlantic spider crabs have been spotted near the Antarctic Peninsula. These species probably traveled in a ship’s ballast tank and were released as the tank’s water was emptied.


Annual bluegrass, commonly used in putting greens, is now making its way to Antarctica: Courtesy of Ian Britton and freefoto.com

Global warming isn’t helping this invasive species problem. Globally, we see a greater biodiversity of organisms at the tropical regions than we do the polar regions. As the temperatures increase and the ice melts away on Antarctica, the warmer climate will allow for the survival of a broader range of organisms.

Jul
06
2006

Global Warming: NASA photo of Earth taken from Apollo 17
Global Warming: NASA photo of Earth taken from Apollo 17

Have you been following the comments in Cari's Buzz Blog post about Gore's movie, An Inconvenient Truth. I find it interesting that very intelligent people can look at the same data ("truths") and yet totally disagree as to what to accept as reality?

A Global Warming Skeptic Challenge

George Musser on the Scientific American Blog has been moderating a discussion about global warming titled Are You a Global Warming Skeptic? Part IV He started the discussion March 6, 2006 with this statement:

In the comments field, explain which aspects of climate change you don't accept (e.g. you might not think Earth is warming at all, you might not think the warming is due to greenhouse gases, you might not think that the gases are produced by humans, or you might not think warming will cause trouble in the future), what exactly has led you to this conclusion, and -- most important -- what it would take to convince you otherwise. Let's get everything out into the open, so that we can have a real discussion.

The discussion is presented in four parts with hundreds of comments. I am recommending this thread because Musser first listens to, then presents a summary of the skeptics' arguments. I find the fairest way to make up my mind on an issue is to thoroughly understand both sides of the argument. Musser explains how scientists crunch the various data to answer difficult questions. He uses the analogy of examining fingerprints during a crime scene investigation.

Climatologists have maps and time series showing how a boatload of climate variables -- mean temperature, temperature ranges, air pressure, precipitation, and so on -- vary in time and in space, horizontally across the surface and vertically through the atmosphere. These data sets are a gold mine for resolving ambiguity, because the different forcings leave distinct fingerprints. Such patterns make it possible to tease out their relative contributions. Over the years, researchers have considered ever more variables besides temperature and ever more forcings besides greenhouse gases. They have merged spatial and temporal patterns, looked at regional as well as global scales, and developed more sophisticated mathematical tools.

View from the Crime Scene

"Fingerprints" included solar variability, volcanic eruptions, greenhouse gasses, ozone, aeosols, and various generic effects. When climatologists run the fingerprinting analysis for different historical epochs, they find that temperature fluctuations prior to the Industrial Revolution were driven primarily by solar and volcanic forcings. In the early 20th century, natural and anthropogenic forcings seem to contribute equally. From midcentury onwards, greenhouse gases rule(temporal pattern). Since 1979, when continuous satellites observations began, the surface and troposphere have warmed and the stratosphere has cooled(vertical pattern). Pretty much the entire surface has gotten warmer, high latitudes more than lower ones(horizontal pattern). All the oceans have warmed; there isn't the zero-sum game of warming and cooling you'd expect from natural variability(energy variability).

Musser concludes,

"unless I'm missing something, it seems to me that the case for anthropogenic warming is pretty strong...Based on the knowledge we have so far, however, I have to call 'em as I see 'em."

To appreciate the use of critical thinking and scientific method I recommend wading through the four installments of "Are you a global warming skeptic?" Part I (673 words); Part II (2219 words); Part III (2617 words); Part IV (3516 words); and an Appendix