Climate Change

Creating the right atmosphere: How should carbon-emissions permits be allocated?

dianeb — Wed, 07 Oct 2009 16:56:28 -0600

If you had an asset worth billions of dollars, would you give it away free? No? Would you hand it over if charging for it would clobber farmers with added expense, hobble businesses in similar fashion, boost unemployment and raise the cost of living for just about everyone?

To hear policy wonks and special-interest types spin it, those are the consequences lawmakers face in considering an allocation scheme for carbon-emission permits. And, right now, some 85 percent of the permits that will give utilities and other organizations the right to emit greenhouse gases into the atmosphere are going to be given away free of charge. Is that allocation scheme in the best interest of U.S. citizens? That's one of the questions legislators will consider in coming months.

Musical chairs
In economics, allocation is how we determine who gets what. "The reason we talk about allocation is because not everyone gets what they want," explains William Boyes, an economics professor at the W. P. Carey School of Business. "There is a limited supply of resources, and we have to figure out the best way to distribute those resources to the people who want them."

According to Boyes, everything is allocated in four major ways. One is first-come, first-served, which is how, for example, we gain entry onto the highway, get that kidney transplant we've been waiting for or snag a seat in a game of musical chairs.

Or, you can allocate resources by random chance, such as what happens when people buy tickets to a state lottery.

Markets are allocation engines, too. As Boyes explains, markets distribute resources according to "people's ability and willingness to pay for them."

Governments get into the allocation game, as well. They divvy out things like welfare benefits, water-tap rights and fishing permits. And, speaking of permits, under H.R. 2454, a piece of legislation passed in the U.S. House of Representatives last June, the government would grant businesses and utilities permits to emit limited amounts of greenhouse gases, such as carbon dioxide and methane. The American Clean Energy and Security Act of 2009, dubbed the Waxman-Markey Bill in honor of its sponsors, institutes a "cap-and-trade" system designed to lower greenhouse gas emissions overall.

Cap-and-trade systems offer economic incentives for lowering emissions of pollutants. Under House Bill 2454, the government will limit, or cap, the total amount of greenhouse gas emissions businesses are allowed to release into the atmosphere, then issue permits allowing businesses to emit a share of that total. Those that emit less than their allowance are free to sell the leftover amount to businesses that will exceed their permitted amount of emissions. That's the trade part of cap-and-trade legislation.

Similar legislation was put in place by the Clean Air Act Amendments of 1990, which set a goal of combating acid rain by reducing sulfur dioxide emissions to 10 million tons below 1980 levels. The landmark cap-and-trade approach was successful in achieving that goal. In 1980, U.S. industry coughed more than 17 million tons of SO2 into the air, according to the U.S. Environmental Protection Agency. By 2008, emissions were down to 7.6 million tons.

Moving from regulation to a market-based system requires three things—a decision of how much to emit each year in total; a decision of who gets to emit how much of that total or who gets the permits; and finally how, if at all, do they pay for them. Trading among firms from that starting point is how a market system aligns incentives. Those who can control at least incremental cost will sell off their excess permits to those who cannot.

Boyes sees a market-based approach as "the efficient" means to organize those exchanges. But, in the case of pollution permits, the government starts the process by allocating the permits initially, and then deciding how much they pay for them. In general, markets are efficient at organizing the exchanges. All the other allocation approaches are "inefficient, meaning they waste resources," he says. According to him, "When the government allocates the initial set of permits, people spend resources lobbying the government. If it's first-come, first-served, they all race to grab their share."

Boyes doesn't see random lotteries as the answer, either. "Someone who doesn't need a permit will get one, and someone who really needs one won't," he predicts.

"Price-based allocation means the businesses will choose the most efficient way to use their resources. If it's less expensive for them to buy new equipment and sell their permits, they'll do that. If it's less expensive to buy permits and not improve equipment, they'll do that," he says. "As the number of permits goes down and permit prices go up, it induces people to use more efficient production technologies. The market system is what works best."

That's why he thinks that if the government is going to get into the pollution permit business, the market system is probably the best way to allocate those permits.

But, how do we get those permits into a market to begin with?

Pay to play
Should the government sell the permits and generate revenue? Or give them away, as it did with most of the SO₂ permits issued to comply with the Clean Air Act?

That's a question of great interest to carbon emitters, such as electric utilities. According to government data, energy-related carbon dioxide emissions represent more than 82 percent of total U.S. human-produced greenhouse gas emissions, and electric utilities produce 40 percent of those carbon emissions.

Not surprisingly, electric utilities are hoping the government will simply give the emission allowances away. And, that's what will happen with 85 percent of the emission allowances if the allocation details of H.R. 2454 prevail in a Senate bill, notes Kerry Smith, a professor of economics at the W. P. Carey School of Business.

Analysts for the Edison Electric Institute, a trade group representing 70 percent of the power industry, have issued a number of policy statements on the allocation issue. According to them, the disbursements based on historical levels of emissions are important "consumer cost-containment measures." The EEI commentary suggests that if Congress gives the permits away, electricity costs won't be as likely to rise, or they might not rise as dramatically.

"That is nonsense. If I give away 100 new laptops to 100 incoming freshman, do you think those who receive the free laptops and already have one will simply give it away to another student? I don't think so—they will make use of E-Bay and sell the one they don't want" says Smith. "There is a fiction that giving the permits away holds down costs. We regular citizens will pay for the costs of control soon after the permits are given out as we pay for gasoline and electricity."

Smith points out that the price of electricity produced in large part from coal did not remain constant after the sulfur dioxide emission permits were handed out gratis. Many firms had to wait for approved rate hikes, but they did increase prices and lobbied commissions to be allowed to sell their permits when they could control sulfur at lower costs.

"Prices for these permits tell us how difficult it is to control emissions," he said "According to data from the financial firm of Cantor Fitzgerald, the price per ton for SO₂ was around $200 in January of 1993. By January of 2007, it was around $600 per ton, and it spiked to $1,600 per ton in January of 2005. The spike was due to anticipated changes in the national emission target, a proposed tightening in the sulfur dioxide cap. Permits could be banked. Firms that didn't need their permits certainly did not give up $1,600 per ton and hand them over gratis to a competitor. Utilities had to pay, and they passed the costs along to consumers."

So, according to Smith, the best approach would be to have an auction and allow utilities to buy the permits from the government. "We're trillions of dollars in debt, and we're giving these permits away?" he asks.

Smith also recognizes that "people say costs will rise, and industry will go in the tank." He has a simple solution: "Have an auction and declare a price cap for permits each year—because we do not have experience with control costs in advance. If bids go over the price cap, we sell as many permits as needed that year at the price cap. Everyone knows what to expect and we have a clear path for the extent of cost increase." He notes that this kind of approach will reduce uncertainty among permit-buyers while ensuring that the revenue from the auctions goes to the American public.

"The question is who owns the permits," he continues. "My perspective is that the citizens of the United States own those permits. Our representatives are giving them away and telling us this is to hold down costs. That's just nonsense."

Watts the Cost?
Smith isn't the only one who thinks electricity prices will rise under H.R. 2454, even though the legislation currently calls for some 85 percent of those permits to be given away free of cost.

Ben Lieberman, a policy analyst for the Heritage Foundation, sees electricity costs rising dramatically under the bill. He said as much in testimony before the House and Senate Western Caucus this past July.

Noting that the bill's provisions go into effect in 2012, Lieberman predicted that a household of four would see energy costs rise $436 that year. "Electricity costs will go up 90 percent by 2035, gasoline by 58 percent and natural gas by 55 percent," he warned.

"Since higher energy costs raise production costs," the price of everything else will rise, too, he added. In fact, he projected the cost of Waxman-Markey to be "an average of $2,979 annually from 2012 to 2035 for a household of four."

The Congressional Budget Office (CBO) disagrees. According to its June 2009 assessment, H.R. 2454, as now written, would incur additional economy-wide costs equal to approximately $175 per household in 2020. That's an average, the CBO notes. Households in the highest income quintile would each see a net cost of $245, while those in the lowest income quintile would see an average net benefit of about $40.

Of course the control of emissions is being considered for important reasons and that often gets lost in the wake of competing claims about costs, giveaways and so forth. Greenhouse gases accumulate in the atmosphere for decades. They appear to be changing our climate system. We can expect those changes will be with us for a long time. They will be different depending on where you live. Right now the effects of these accumulations are also very uncertain. It turns out that these considerations are what need to be assessed to measure the benefits from controlling greenhouse gases. The EPA, CBO and Energy Information Administration all crunched numbers to pinpoint the cost of complying with Waxman-Markey, but none of them factored in the benefits of climate-change abatement.

Along with costs of cap-and-trade legislation, special-interest groups are urging policymakers to think about job losses. Jay Timmons and David N. Taylor, two representatives of manufacturing trade groups, wrote a Labor Day opinion piece for The Philadelphia Inquirer. In it, they warned that Waxman-Markey could slash 97,500 jobs out of the Pennsylvania economy by 2030, "even when 'green jobs' created are accounted for." Nationally, the team predicts 2.4 million jobs will be sacrificed due to the legislation's high costs for compliance.

The legislation is sowing seeds of stress for farmers, too, mostly because it targets methane—an animal byproduct. The W. P. Carey School's Smith reports that lawmakers considered treating the emission permits associated with agriculture differently and giving the Department of Agriculture control over the agriculture sector's share, rather than EPA which would administer the rest. He called the idea "terrible—one market, but different agencies deciding what counts and handing out permits. That's a non-starter."

Speaking of farming, where do carbon offsets come in? That, Smith points out, will be one of the issues to consider in answering allocation questions. So, for instance, planting trees creates a "carbon sink," a reservoir that accumulates carbon and keeps it out of the atmosphere. If someone already has land that's covered with trees, should they get offset credits? "Hopefully not," would be Smith's answer. Or, would existing forests be exempt, because they're not new reductions to greenhouse-gas emissions? And, he continues, "Who decides what counts" with offsets? He says emission offsets should come under the same agency regulation as permits "to emit, and they should have the same price in annual terms when they are equivalent to a reduction in a ton of emissions."

So, we know there are clearly going to be impacts—on everything we do, including agriculture. But we don't yet know the extent of the impact, so it's hard to assess how much we would pay to avoid it.

What's certain is grumbling. "Consumers want lower prices," says Boyes. "They don't want pollution, but they don't want to pay the cost of reducing it."

How will those divergent attitudes be reconciled?

"They won't," Boyes concludes.

This story first appeared on the Knowledge@W.P. Carey web site.

Too hot to handle

dianeb — Mon, 15 Jun 2009 11:23:50 -0600

by Diane Boudreau

Summertime rolls into Phoenix, Arizona to as much welcoming fanfare as a pimple on prom night. While people in other parts of the country head outdoors for picnics and baseball games, Phoenicians hole up in air-conditioned buildings as temperatures soar above 100 degrees F for months at a time.

Some years are worse than others. In July 2005, Phoenicians sweltered through nine consecutive days that topped 110 degrees. At least 21 people died as a result of that heat wave, one of the worst in the area’s recent history.

Obviously, homeless people and undocumented immigrants crossing the desert borderlands are at especially high risk during these heat waves. But the results of a new study show that even low-income people with homes are more vulnerable to the heat than wealthier folks. The reason has to do with what scientists call the “heat island effect.”

The Sonoran Desert is known for its hot, dry climate. But Phoenix gets an extra helping of heat because it is an urban heat island. In the desert wilderness, hot summer days turn into cooler nights when the sun sets. But in cities, structures such as buildings, roads, and parking lots retain daytime heat. As a result, the temperature is ratcheted up even in the dark of night. The city transforms into an “island” of heat.

The Phoenix heat island isn’t uniform. Within its boundaries, temperatures vary widely from neighborhood to neighborhood. It turns out that people living in the warmest neighborhoods typically have lower income than people living in cooler neighborhoods. The warmer neighborhoods also tend to have higher minority and elderly populations.

This map of temperature variability throughout metropolitan Phoenix shows significant differences in temperature distribution. Red areas represent the hottest temperatures. The dots represent the study neighborhoods.

“There are significant differences in temperature even within a metro area and that’s correlated with humans—the people that live in those areas,” says Darren Ruddell, a former Arizona State University doctoral student who led the study. “It’s an environmental justice issue. The people who are most vulnerable are also living in the worst conditions. It’s a double whammy.”

Sidewalks are for frying eggs
The reason why has to do with land cover—the things people place or plant on the ground. Ruddell studied temperature and land cover in 40 different neighborhoods throughout the Phoenix metro area from July 15 to July 19, 2005. He divided land use/land cover into four categories:

urban (commercial/industrial)
xeric (residential drought-resistant landscaping)
desert (undisturbed natural land)
mesic (residential with mostly grass landscaping)

Ruddell determined daytime and nighttime temperatures using data from the Weather Research and Forecasting model developed by the National Center for Atmospheric Research. Susanne Grossman-Clarke is a researcher in ASU’s Global Institute of Sustainability. She calibrated the model for metro Phoenix and ran the simulations. Ruddell compared temperature readings from local weather stations to the model to ensure its validity.

He also analyzed census data on population, income, ethnicity, and age for each of the neighborhoods he studied. Ruddell compared the temperature and census data to land use information taken from satellite images.

This image represents the amount of exposure to extreme heat (113 F or more) among the 40 neighborhoods.

The results showed that urban and xeric landscapes were hotter than mesic and desert areas. This might come as disappointing news for people trying to help the environment by xeriscaping their yards. Ruddell says that xeriscaping might not be the best environmental decision in the long run.

“You change the landscape and then these neighborhoods become hotter. So people use the air conditioner more and for longer periods,” he says. “And water is used in generating the electricity that runs the air conditioner.”

In low-income neighborhoods, neither grass nor desert landscapes are common. Instead, these areas sport layers of concrete or simply bare soil. These are the hottest neighborhoods of all. And their residents are the least likely to have the resources to combat the scorching temperatures.

Is it getting hot in here?
In 2006, more than 800 Phoenix area residents shared their perceptions about heat in a survey developed by Sharon Harlan, a professor at ASU’s School of Human Evolution and Social Change. Harlan’s Phoenix Area Social Survey asked residents if they think Phoenix is getting a lot hotter, a little hotter, or not hotter at all. It also asked them to compare their neighborhoods’ temperatures with other neighborhoods in the metro area.

Ruddell compared these answers with the temperature data. He found that perceptions were very accurate on the neighborhood scale. People living in cooler neighborhoods perceived their local environments as cooler and people living in warmer neighborhoods perceived their environments as warmer. But perceptions became less accurate on a regional scale.

“People can perceive climate change when they experience it,” says Ruddell. “People’s perceptions of environmental conditions become increasingly distorted as the scale broadens, however. If you continue that out to the global scale, people don’t perceive global climate change very well at all.”

The survey also asked residents if anyone in their households had experienced heat-related symptoms—such as leg cramps, fatigue, or fainting—during the summer of 2005. Ruddell noticed a spike in the number of symptoms in the very hottest areas. The results suggest that there is a tolerance threshold for heat.

Ruddell hopes the information from his study can help Phoenix area residents to avoid heat-related health problems. One way to do this would be to redesign neighborhoods.

“If we know that green space or shade could relieve heat stress we could change the design of neighborhoods,” he suggests.

However, Ruddell adds that redesigning neighborhoods is not as simple as it sounds. Growing trees requires time and money, but time and money don’t grow on trees. Many low-income residents can’t afford to water plants and don’t want to mow lawns after working multiple jobs.

Another possibility is improving heat wave warning systems. “Right now the heat wave warning systems aren’t that effective,” says Ruddell. “They’re applied at really broad scales. With the information that we have we could be a lot more effective. We could identify areas that are vulnerable and set up aid stations.”

Ruddell received his doctorate in geographical sciences from ASU in Spring 2009. But he is still working with ASU researchers to study water use and temperature on a household level. The scientists hope to learn the best way to landscape to minimize water use while maximizing the cooling effects of plants.

“I think we can design cities better to help reduce the intensity of urban heat islands as well as reduce human vulnerability to heat,” he says.

The research is based on projects that were funded by the National Science Foundation. Darren Ruddell’s study is being published as a chapter in the upcoming book Geospatial Contributions to Urban Hazard and Disaster Analysis. Collaborators on the project include faculty advisor Elizabeth Wentz, ASU School of Geographical Sciences and Urban Planning; Sharon Harlan; Susanne Grossman-Clarke; and Alexander Buyantuyev, a former doctoral student in the School of Life Sciences.

Another step towards forecasting global warming

ovprea — Mon, 18 Aug 2008 12:23:09 -0600

Arizona State University researchers have made a breakthrough in understanding the effect on climate change of a key component of urban pollution. The discovery could lead to more accurate forecasting of possible global-warming activity, say Peter Crozier and James Anderson.

Crozier is an associate professor in ASU's School of Materials, which is jointly administered by the College of Liberal Arts and Sciences and the Ira A. Fulton School of Engineering. Anderson is a senior research scientist in the engineering school's Department of Mechanical and Aerospace Engineering.

As a result of their studies of aerosols in the atmosphere, they assert that some measures used in atmospheric science are oversimplified and overlook important factors that relate to climatic warming and cooling.

The research findings are detailed in the Aug. 8 issue of Science magazine, in an article co-authored by Crozier, Anderson and Duncan Alexander, a former postdoctoral fellow at ASU in the area of electron microscopy, and the paper's lead author.

So-called brown carbons—a nanoscale atmospheric aerosol species—are largely being ignored in broad-ranging climate computer models, Crozier and Anderson say.

Studies of the greenhouse effect that contribute directly to climate change have focused on carbon dioxide and other greenhouse gases. But there are other components in the atmosphere that can contribute to warming#151;or cooling—including carbonaceous and sulfate particles from combustion of fossil fuels and biomass, salts from oceans and dust from deserts. Brown carbons from combustion processes are the least understood of these aerosol components.

The parameter typically used to measure degrees of warming is radiative forcing, which is the difference in the incoming energy from sunlight and outgoing energy from heat and reflected sunlight. The variety of gasses and aerosols that compose the atmosphere will, under different conditions, lead to warming (positive radiative forcing) or cooling (negative radiative forcing).

The ASU researchers say the effect of brown carbon is complex because it both cools the Earth's surface and warms the atmosphere.

"Because of the large uncertainty we have in the radiative forcing of aerosols, there is a corresponding large uncertainty in the degree of radiative forcing overall," Crozier says. "This introduces a large uncertainty in the degree of warming predicted by climate change models."

A key to understanding the situation is the light-scattering and light-absorbing properties—called optical properties—of aerosols. Crozier and Anderson are trying to directly measure the light-absorbing properties of carbonaceous aerosols, which are abundant in the atmosphere.

"If we know the optical properties and distribution of all the aerosols over the entire atmosphere, then we can produce climate change models that provide more accurate prediction," Anderson says.

Most of the techniques used to measure optical properties of aerosols involve shining a laser through columns of air.

"The problem with this approach is that it gives the average properties of all aerosol components, and at only a few wavelengths of light," Anderson says.

He and Crozier have instead used a novel technique based on a specialized type of electron microscope. This technique—monochromated electron energy-loss spectroscopy—can be used to directly determine the optical properties of individual brown carbon nanoparticles over the entire visible light spectrum as well as over the ultraviolet and infrared areas of the spectrum.

"We have used this approach to determine the complete optical properties of individual brown carbon nanoparticles sampled from above the Yellow Sea during a large international climate change experiment," Crozier says.

"This is the first time anyone has determined the complete optical properties of single nanoparticles from the atmosphere," Anderson says.

It's typical for climate modelers to approximate atmospheric carbon aerosols as either non-absorbing or strongly absorbing. "Our measurements show this approximation is too simple," Crozier says. "We show that many of the carbons in our sample have optical properties that are different from those usually assumed in climate models."

Anderson adds, "When you hear about predictions of future warming or changes in precipitation globally, or in specific regions like the Southwestern United States, the predictions are based on computer model output that is ignoring brown carbon, so they are going to tend to be less accurate."

The research was funded with grants from the National Science Foundation (NSF) Chemistry Program and the National Aeronautics and Space Administration (NASA) Radiation Science Program.

The work is part of the Aerosol Characterization Experiment (ACE) program. Crozier and Anderson have been involved in the U.S. component of the ACE-Asia experiment, a large-scale, multi-agency effort to characterize aerosols from East Asia, involving the NSF, NASA, the National Oceanic and Atmospheric Administration, the Department of Energy and others.

For more information, contact Joe Kullman, Ira A. Fulton School of Engineering, 480.965.8122. Send email to joe.kullman@asu.edu

Warmer at the bottom of the world

ovprea — Sat, 13 Jan 2007 13:03:45 -0700

by Adelheid Fischer

It is January 2004, the height of the Antarctic summer. A snapshot by National Geographic photographer Peter Essick captures Tad Day wearing a look of pure concentration as he presses close to the ground of Anvers Island. Bareheaded and ungloved with pencil and notepad in hand, the botanist gently pries apart the stalks of tiny tundra plants that grow in the rubble of this island off the coast of the Antarctic peninsula.

Although the cloudless morning seems downright balmy, it is not without a sense of urgency. As he peers into the jumbled carpet of hair grass, pearlwort, lichens and mosses, Day's head is slightly cocked. It's as if he were listening for icebergs calving from a nearby glacier.

Five miles of open water separate the island from a hot shower and dry bed at Palmer Station, the base camp for scientists visiting the western coast of Antarctica. A small shift in the wind could quickly corral the sea's far-ranging floes and push them to shore, creating an impassable field of grinding ice.

"You get engrossed in work and don't pay attention," says Day, a professor in the School of Life Sciences at Arizona State University. "The next thing you know, you're asking, Where did the ocean go? You look out and there's nothing but miles of white."

But shifting ice isn't the only thing that lends urgency to Day's work. It was 1994 when he made his first research foray to the frozen continent. He recalls reading an obscure scientific paper warning that Antarctic temperatures were on the rise.

"I thought, maybe somebody would be golfing down there in a thousand years or so," he says. Of far greater concern to Day and his fellow scientists at the time was the thinning in the Earth's protective ozone layer every spring and early summer over Antarctica. Back then, Day examined the ways in which Antarctic plants coped with the excess dose of damaging ultraviolet radiation that streamed through the ozone hole.

But subsequent research has shown that the temperatures of Antarctica are climbing far more steeply than initially noted–up to 10 times the global average, according to some estimates. The unprecedented opportunity to document plant communities in one of the most rapidly warming regions on Earth prompted Day to enlarge the focus of his research. Today, he and his team of graduate students are studying the dance of tundra and ice as they move across the landscape in response to the accelerating beat of warming temperatures.

Antarctica: Then and Now

The changes have caught even veteran scientists such as Day off guard. One of the most surprising developments is the sheer amount of new real estate that has been newly vacated by the glaciers. Travel to some of his research sites, Day points out, once entailed navigating the team's Zodiac boat along a wall of ice some five stories high.

Today, the glacier has largely given way to rocky beach. The transformations are so pronounced that Day has been forced to revamp the maps of his study sites that were drawn from aerial reconnaissance in the 1990s. Jutting fingers of land have become islands seemingly overnight as connecting bridges of solid ice have melted away.

"One of the things that's shocking to me is how quickly it's warmed down there," he says. "I never thought I'd see such big changes in my lifetime."

Terrain that hasn't seen sunlight for thousands of years now is being claimed by tundra plants with a speed that astonishes Day and his team.

Take Point 8, for example, a recently deglaciated spit of land on Anvers Island. On a survey of the point in 1995, the researchers could find no trace of Antarctic hairgrass and Antarctic pearlwort, the only two flowering plants that are native to the continent. But by 2004, nearly 300 pearlwort plants had taken root; the hairgrass population soared to more than 5,000 plants. So lush was this growth that, from a distance, some stretches of rock rubble looked as if they were covered with a layer of turf, Day says.

What accounts for the exponential increase? For one thing, Antarctic plants benefit from a ready supply of nutrients, such as nitrogen and phosphorus that are far more limited in polar regions of the north. The difference, Day speculates, is due to the fertilizing guano that is supplied by large numbers of marine birds such as gulls, penguins and skuas, as well as mammals such as seals.

On the Antarctic Peninsula, Day says, "You're never far from a penguin or a seal or a gull. There are so many of them around."

Day's experiments have demonstrated that warmer temperatures sharply increase the odds that seeds will be able to take advantage of these nutrient stores. In a series of plots constructed behind Palmer Station, Day's team has recreated what he calls a "microcosm of the tundra."

The experiment includes 240 cores of mature tundra that were excavated from a separate field site some eight miles away. Using infrared heaters, the team is able to carefully control temperatures as well as calibrate inputs such as rainfall. Funnels capture leachate from the tundra plugs so that the researchers can measure the amount of carbon and nitrogen that leaves the system. In this way, they can test the response of tundra plants to a variety of global warming scenarios.

Results show that even a warming of just one degree Fahrenheit can dramatically boost the number of viable seeds that tundra plants produce.

For example, a single pearlwort plant can sprout hundreds of tiny flowers. But only a fraction--eight seeds per square centimeter–will mature and be viable before summer's end and the return of snow in March. A small increase in temperature boosts the number of viable seeds that plants produce to more than 150. The reason, Day says, is that warmer temperatures allow more flowers and their seeds to mature before the end of the growing season.

With the combined advantages of soil nutrients and warmer temperatures, tundra plants have invaded large stretches of newly deglaciated Antarctic terrain. But Day cautions that the continent is not likely to become a golfing destination any time soon.

Warmer temperatures cause greater evaporation. More moisture in the air leads to heavier precipitation. As a result, the region's winter snow pack appears to be increasing along with its temperatures. Plants that have colonized areas prone to snow accumulation can be wiped out in a few years of above average snowfall.

"You can have an area the size of half a city block covered with plants and then two years later not a single plant is alive," he explains. "That's the flip side of warming for the plants down there."

The ebb and flow of these tiny plants in a remote Antarctic outpost could help researchers shed light on the larger problem of global climate change. Day notes that climate scientists have a fairly accurate tally of the amount of carbon dioxide that is emitted into the atmosphere from the burning of fossil fuels by automobiles, say, or coal-fired power plants. (CO₂ is a major greenhouse gas that causes global warming.)

Whether the Earth's large natural ecosystems, such as rainforests, boreal forests, tundra or grasslands, will contribute to the buildup of atmospheric CO₂, or serve as critical storage, remains a wild card.

In the Arctic, for example, scientists have found that warming temperatures are causing deep layers of frozen peat, known as permafrost, to thaw. The stepped-up microbial activity in this peat is releasing significant amounts of CO₂, thereby hastening further global warming.

According to Day, the melting of the Antarctic tundra is not likely to send vast concentrations of CO₂ into the atmosphere since the thickest permafrost measures no more than one foot deep. In addition, higher temperatures appear to stimulate plant growth, causing them to take in more atmospheric CO₂.

Still, he cautions, little is known about the Antarctic tundra ecosystem despite the fact that it hosts only a sparse sampling of plants and an equally bare-bones suite of animals including microbes, several species of springtails and mites, as well as a wingless midge that Day jokingly refers to as "the largest land animal native to Antarctica. It's at the top of the food chain."

Day's research has made one thing clear, however: the plants have a definite thermal threshold. When temperatures get too warm, they simply shut down operations. If he has learned anything from his many trips to Antarctica, it's that major ecosystem change can be triggered with the proverbial flip of a switch.

Already, he says, some organisms such as Adele penguins appear to be dropping out of the mix along the Antarctic peninsula. Their numbers have plummeted from several thousand in the 1990s to some 500 animals today. The decline is largely due to the increased incidence of early season storms that bury their shore-edge nests in great drifts of snow.

"There's a lot of skepticism and public misunderstanding about global change issues and greenhouse warming. There's so much misinformation out there," Day says. "This is a great story for what can happen and there are some valuable lessons."

ASU research projects in Antarctica are supported by the National Science Foundation. For more information, contact Thomas A. Day, Ph.D., School of Life Sciences, 480.965.8165, or email tadday@asu.edu