Discovery News: Environmental

Mussel Bound

Jennifer Viegas wrote a great story about the decline of a critical Great Lakes crustacean, probably because of invasions of zebra and quagga mussels in the Great Lakes.

These troublesome mussels are no longer limited to the Great Lakes region. In January 2007 quagga mussels were first found west of the Continental Divide in Lake Mead, Nev. They have since moved downstream in the Colorado River and into California, where they threaten to clog the waterworks that supply drinking water to millions.

The zebra mussel turned up in California in 2008.

The U.S. Geological Survey now tracks these invaders in an interactive Google Map updated daily (zebra mussels here and quagga mussels here). See where they’ve spread.

"We really want people not to spread these around," said Amy Benson of the USGS in Gainesville, Fla. "If you can look at our map and see that they’re in this lake, then you might not go fishing there."

"The public is so important in this," she added.

(Images: Instrument encrusted with zebra mussels, Lake Michigan, NOAA. Benson, A. J. 2008. Zebra mussel sightings distribution. Retrieved 31 May 2008 from here.)

 

How Green Is Your Hometown?

The Brookings Institution today released a report ranking the nation’s 100 biggest metropolitan areas by their residents’ average carbon footprint—the amount of CO2 they are responsible for releasing based on vehicle transportation (including freight and personal) and home energy use.

City living is greener overall: Although two-thirds of the U.S. population lives in the 100 biggest urban areas, they are responsible for only 56 percent of the carbon emissions. These urbanites’ footprint is 14 percent less than the country average.

So… who are the winners and losers?

Here are the 10 metropolitan areas with the lowest carbon footprint…and the highest (per capita CO2 emissions in metric tons in parentheses):

BEST
1.  Honolulu, HI (1.356)
2.  Los Angeles-Long Beach-Santa Ana, CA (1.413)
3.  Portland-Vancouver-Beaverton, OR-WA (1.446 )
4.  New York-Northern New Jersey-Long Island, NY-NJ-PA (1.495)
5.  Boise City-Nampa, ID (1.507)
6.  Seattle-Tacoma-Bellevue, WA (1.556)
7.  San Jose-Sunnyvale-Santa Clara, CA (1.573)
8.  San Francisco-Oakland-Fremont, CA (1.585)
9.  El Paso, TX (1.613)
10. San Diego-Carlsbad-San Marcos, CA (1.630)

WORST
91.  Knoxville, TN (3.134)
92.  Harrisburg-Carlisle, PA (3.190)
93.  Oklahoma City, OK (3.204)
94.  St. Louis, MO-IL (3.217)
95.  Nashville-Davidson--Murfreesboro, TN (3.222)
96.  Louisville, KY-IN (3.233)
97.  Toledo, OH (3.240)
98.  Cincinnati-Middletown, OH-KY-IN (3.281)
99.  Indianapolis, IN (3.364)
100. Lexington-Fayette, KY (3.455)

Here in Minneapolis-St. Paul we rank 45th.

How dense the city is, how much home heating and cooling the city requires, and whether the city uses primarily coal or a less carbon-intensive form of energy all contribute to where it sits in the green rankings.

Check out the whole report here (click on "Download"), and the complete rankings, clicking on "Download  Per Capita Footprints Supporting Material."

Atmospheric Scientists: To Study CO2 Is to Spew It

Here’s a curious article from the Annals of Irony: “The travel-related carbon dioxide emissions of atmospheric researchers.”

Andreas Stohl of the Norwegian Institute for Air Research (NILU) in Kjeller, Norway calculated the CO₂ emissions from all business travel for the institute's scientists, who study air pollution, including climate change.

More than 90 percent of the emissions came from air travel. The annual total for business travel alone came to 4.3-6 tons per scientist, compared to the global average annual total per capita CO₂ emissions of 5 tons.

"The travel-related CO₂ emissions of a NILU scientist, occurring in 24 days of a year on average, exceed the global average annual per capita emission," Stohl pointed out.

Incredibly, the Norwegian average annual total per person is 21 tons, among the highest in the world, Stohl reported, mostly because of oil industry emissions.

However, he concluded in his abstract (which was actually published in Atmospheric Chemistry and Physics Discussions), “If the emissions per NILU scientist derived in this paper are taken as representative for the average Norwegian researcher, travel by Norwegian scientists would nevertheless account for a substantial 0.2% of Norway's total CO₂ emissions. Since most of the travel-related emissions are due to air travel, water vapor emissions, ozone production and contrail formation further increase the relative importance of NILU's travel in terms of radiative forcing.”

As someone who works from home and sometimes gets a little stir crazy, I can see the benefits of face-to-face contact, and if these researchers' flights are going to help solve the climate problem sooner, then they're probably worth the CO₂. But video conferencing is getting more and more sophisticated—and is being used more as fuel and flight prices go up.

Should we be pushing for more telecommuting or do we need to meet in person? Let us know about your telecommuting successes and failures.

(Photo: NOAA via Wikimedia Commons)

Where Will the "Killer" Bees Go?

Here are some graphics to accompany today's story about NASA researcher Wayne Esaias's trying to predict the spread of Africanized bees using satellite data and a network of weighed beehives.

First, here's the bees' current range according to the USDA:

Now, here's the new map that researchers Catherine Jarnevich and Tom Stohlgren at USGS created with contributions by Pete Ma at NASA Goddard:

The second map was created by overlaying today's climate data with the existing Africanized bee range (hatched area), and using a model to identify suitable habitat based on the characteristics of where the bee already lives.

This map does not yet include any of the satellite data or bee forage information that Esaias plans to incorporate, but, according to Esaias, "Nevertheless, this is a significant new map, of use to state managers and beekeepers, until the improved version is ready."

As noted in the story, some of the notable range expansions are up the California Central Valley and into Georgia. Notable lack of expansion is much of the East. The bees are aggressive, so if they move in, beekeepers have to adjust. "I could not keep Africanized bees in my backyard. It's too dangerous and irresponsible," Esaias said.

According to Esaias, "A lot of the queens that are used to replace the dead colonies [from colony collapse disorder and mite infestations] are raised in Mississippi, Alabama, Georgia and Texas. They raised about 2.5 million queens a year." For those bees to become heavily Africanized would be a problem for the nation's bee industry.

The map is good news for Esaias. He should be able to keep his backyard hives if his early predictions are correct: Maryland appears to be a safely blue zone.

(Images: USDA and USGS & NASA Goddard, via Wayne Esaias)

 

Spring on a Sphere

It amazes me how much growth can happen in such a short time. In the last couple of weeks, the view out my window has exploded in green. Fleshy leaves have erupted from bulbs underground, and great slabs of chlorophyll now cover the trees. It’s no wonder atmospheric levels of CO2 take a measurable dive in spring.

You can watch the green of spring seep northward in time-lapse images from space. I saw this at the Science Museum of Minnesota, which has an installation of Science on a Sphere. Science on a Sphere is a simple idea: four computers project various views of Earth onto a white fiberglass globe six feet in diameter, creating amazing time-lapse movies of Earth’s processes. The National Oceanic and Atmospheric Association developed the exhibit, which is on display at 20 places worldwide.

Although far cooler in 3-D, you can watch many of the videos online. The above shows ice extent from satellite measurements, but you can also see greening disappear and then swell northward as the video runs from September 2005-September 2006. (Thanks to NOAA's Beth Russell for creating a custom view for Discovery News.)

Below is a view of carbon dioxide levels. Red is net release. Blue is net uptake. Read a more complete description of what's happening in this movie here.

Enjoy many other movies of the atmosphere, oceans, land, and even other planets by checking out the whole list. Major events are documented, too: you can watch the 2004 tsunami and the Katrina-bearing hurricane season.

(Videos: NOAA Science on a Sphere with data from the National Snow and Ice Data Center and NOAA)

Risk? We Don't Get It.

California residents need to make a plan.

In a scenario released late last week, USGS scientists detailed the predicted fallout from a pretty darned big earthquake on the San Andreas fault. They predicted 1800 dead, and $200 billion in economic damage. That’s not the most likely quake to hit California, but even a smaller quake on the Hayward Fault in the Bay Area could cause plenty of problems.

For the 100th anniversary of the 1906 earthquake, I spent a lot of time researching what might happen in the Bay Area if another big one hit. (Note: earthquake-preparedness proselytizing does not make one popular among friends living near faults.)

One of the things that emerged from conversations with scientists and community leaders is that the inevitable Day the Bay Shakes could be much less catastrophic if people who live there were prepared.

And there is no excuse not to be. We know it’s going to happen someday—more likely than not in the next 25 years —and we know there’s not going to be any warning. So there’s no time like the present to get ready.

Here are some of the things earthquake experts pointed out: Many, many people in the Bay Area cross a fault or two, and a body of water to get to work each day. So, after a big quake they may not be able to get home to their kids or pets for a day or more if roads, subways and bridges are out. They need to have a plan for who will pick up their kids or feed their dog.

Homes may not have water, electricity or gas, so people need to be prepared to live like campers for 3 or 5 days. Imagine the difference in what the emergency response could be if everyone who was OK could just stay at home, self-sufficient, and allow emergency workers to deal with the big problems.

We rely on the ability to tank up the car and hit the ATM. These things may not be possible after an earthquake.

The USGS reported in 2005 that fewer than 10 percent of Bay Area households had a disaster plan and less than half have emergency kits. These stats show just how bad we are at assessing risk and acting accordingly.

This poor ability spills over into tackling environmental problems. Our slow action on climate change is rather like living in California without a disaster plan. A bit of foresight and an eye to the odds could avoid a lot of problems.

(Photo: Statue of zoologist Louis Agassiz on Stanford campus after the 1906 earthquake.)

Meat, Meat, Meat

The take home message from everyone I’ve been speaking with recently is that meat--especially beef--is just no good for the environment.

First, Christopher Weber at Carnegie Mellon University published findings showing that shifting a quarter of the average American’s red meat consumption to other foods saved as much greenhouse gas emissions as going entirely local, i.e. red meat has a really big carbon footprint.

Then, I spoke with researchers highlighting the importance of considering our “nitrogen footprint”, too. “Meat is one of the main drivers of acceleration of the cycle,” said Alan Townsend of the University of Colorado at Boulder. “To have meat diets under modern agriculture takes a lot of nitrogen. You end up having to have a lot of fertilizer and a big chunk of field to grow a few cows or pigs.”

Finally, the Stockholm International Water Institute issued a report about water… You guessed it: meat production takes lot of water. Their report estimates that about 50 percent of calories grown in fields never make it to the table, and about half of that loss is animal feed that doesn’t end up as a calorie on a cow, pig, chicken, or other edible critter. Growing those lost calories takes a lot of water.

For the most part, each of these impacts comes from the same cause: growing a pound of meat requires (much) more than a pound of grain. A pound of beef, for instance, requires eight. (The conversions are better for other types of meat, but never 1:1).

This inefficiency amplifies the demand for nitrogen fertilizer and irrigation, and leads to more of the greenhouse gas emissions associated with growing crops. These emissions come from energy for making fertilizer and release of nitrous oxide (N2O)—a super greenhouse gas almost 300 times more potent than CO2—by bacteria acting on fertilizer in the soil.

With cattle, greenhouse gas emissions also result from methane (23 times more potent than CO2) released by digestion, and nitrous oxide production from manure. 

The SIWI report points out that demand for meat is rising fast. Here are some meat consumption numbers for different parts of the world:

--Southeast Asia: ~88 lbs/person/year in 2002, a sevenfold increase from 1961, when it was 13 lbs.
--India: Projected at 22 lbs/person/year in 2050 (Thanks to a largely vegetarian population.)
--China: Projected at 183 lbs/person/year in 2050
--US: 200 lbs/person/year in 2005, up 22 lbs from 1970

It’s also worth pointing out that dairy creates these impacts, too, though not to the same extent as meat.

Is Grass-Fed Beef Better?
So grain-fed beef is no good… but what about grass-fed? If you read Michael Pollan’s book, The Omnivore’s Dilemma, you might have been convinced, like me, that eating a bit of grass-fed beef was fine--even good. When cows eat grass, they’re converting plant calories that we can’t eat (i.e. grass) into calories that we can. This is an efficient way to harness the energy from the sun in food form in places that aren’t suitable to grow crops.

But, how much does the greenhouse gas footprint change when you switch to grass-fed beef? Then you don’t need those eight pounds of grain. Christopher Weber kindly did some math to help answer this question (Thanks, Christopher!). He cautions that these numbers are approximate and un-reviewed, but here they are:

“By switching to grass fed, you remove around 20% of the CO2 and 60% of the N2O in the supply chain of making and delivering grain to the farms.
So, if there is no increase in methane and manure emissions (of CH4 and N2O) are not being captured at the feedlot, there's approximately a 25% reduction in life cycle greenhouse gas emissions in grass fed vs. grain fed.”

But don’t stop reading. Studies have shown that grass-fed beef produces more methane than grain-fed beef. (Though at least one study has reported the opposite, Weber said.) This offsets some of the gains:

“If the grass-fed has 15% more methane, which is around the number I've seen cited, then grass fed is only 20% better.”

So, while there may be other advantages to eating grass-fed beef over grain-fed, it’s still not a climate-neutral choice. And, as Marshall Burke of Stanford University pointed out, if everyone switched to grass-fed beef, there wouldn’t be enough pastureland to go around.

To the climate conscious: learn to love lentils.

(Photo: Grant Hutchinson)

Water, Water

Today I wrote about a new report that highlights the importance of conserving water globally as demand grows and climate change threatens to disrupt supply.

Folks in my former hometown of Berkeley, Calif., are getting a crash course in water conservation. Last week the East Bay Municipal Utility District rolled out water rationing for the 1.3 million people in their service area, which includes Oakland and Berkeley, in response to two dry years in a row and a snowpack in the Sierra Nevada mountains—a major source of water to the region--at 67 percent of normal.

Following the initial call for residential consumers to reduce water use by 19 percent, plenty of community members complained, saying they already conserve and would have difficulty cutting back further.

They had a point. The top 1 percent of residential users in the area each consume over 1000 gallons a day, about 5 percent of total use, according to EBMUD, while the lowest-consuming 18 percent of users each draw less than 75 gallons a day, about 2-3 percent of the total. The average household in the EBMUD service area uses about 200 gallons of water a day.

In response to complaints, the agency will not require households using less than 100 gallons a day to conserve further. For others, rates will go up 10 percent, and if consumers fail to cut back by at least 10 percent relative to their average usage, they’ll be charged $2 for every 100 cubic feet (748 gallons) they use beyond their allotment.

(I might add that $2 extra for a four-day supply of water really doesn’t seem like a lot. Marshall Burke, of Stanford University, whom I spoke with for the article I wrote today, highlighted this point: “Water is incredibly subsidized. Why should we be growing alfalfa--one of the most water-intensive crops--in the Imperial Valley? It’s because water is so cheap.”)

An article in the San Francisco Chronicle highlights some strikingly different responses to the plan. Here are a couple of excerpted quotes:

"I've got half an acre of lawn, a swimming pool and three teenagers," said Alex Theriault, a contractor from Danville whose bi-monthly water bills top $1,400. "I can't afford not to cut back. But I'm not losing the lawn. My kids like it too much. And I'm not losing the pool. I like the pool."

and

"We've been really lax about water here, compared to other countries," said Debbie Wilson, a mom from Pleasant Hill who brought her children to play in the recycled-water fountain in downtown Pleasant Hill.

"Right now, our automatic sprinklers come on every day," she said. "We'll change that. We need to have water for more important things."

This all gets at the fact that what people consider reasonable conservation varies. A lot. Some people are OK with the “if it’s yellow let it mellow” approach to toilet flushing, while others aren’t willing to lose the lawn, let alone leave pee in the toilet. Much of this is cultural. Depending on who your friends are, peer pressure can push toward greening your lawn, or your lifestyle.

Things like rationing help drive cultural shifts, bringing “fringe” conservation behavior into the mainstream. EBMUD spokesman Charles Hardy told the Chronicle:

"You'd be surprised how many neighbors call in when they've been trying hard to conserve water and they see someone out there washing their car without a shut-off nozzle."

What we need to do is to drive cultural shifts elsewhere—for water, fuel and energy conservation--before rationing is necessary.

(Photos: Milica Tepavac , Ruy Lestrade)

Don't Self-Sequester Carbon

Doing its part?

If you were thinking of sequestering carbon yourself—like, on yourself—by fattening up, you’d better skip it. Of course it’s bad for your heart and your brain and whatever else—but it’s also bad carbon counting.

There’s a letter published this week in The Lancet by Phil Edwards and Ian Roberts of the London School of Hygiene and Tropical Medicine arguing that competition for fuels and food—now widely discussed thanks to the surge in demand for biofuels--is not a new phenomenon. Both agriculture (making fertilizer is energy intensive) and transportation are heavy users of fossil fuels, so rising oil prices affect both.

But the authors also argue that our over-consumption of both food and cars is making us obese, and conversely, that obesity is contributing to climate change and the food crisis.

They write:
Compared with the normal weight population, the obese population consumes 18% more food energy.  Additionally, more transportation fuel energy will be used to transport the increased mass of the obese population, which will increase even further if, as is likely, the overweight people in response to their increased body mass choose to walk less and drive more.

It’s not the first time researchers have made these points. Roberts makes it here and related work is here, but it gets me thinking because I've written about food recently, and come across the statistic that it takes eight pounds of grain to make one pound of cow. Researchers have estimated that the greenhouse gas impact of red meat is 2.5 times greater than chicken or fish.

So I wonder: what’s the carbon footprint of every extra pound we pack? Of course, it depends on whether we’ve made it via beef or beans, but as the authors note, that pound consumes daily metabolic energy, and we drive it around and fly it places. A 2004 study found the average 10 lb weight gain of Americans during the 1990s cost airlines $270 million and released 3.8 million additional tons of CO2 in 2000.

So if I’m going to avoid beef because of its carbon footprint, I’d better cut back across the board, because making an extra pound of me is probably not any greener.

…Now, I also want to know, could carbon offset companies start selling offsets through health clubs or individuals who lose weight and keep it off?

(Photo: James Phelps)

On Thin Ice

Here in Minnesota, it finally feels like spring. Leaves are coming out on the trees and the first flowers are blooming.

It’s spring in the Arctic, too, and that means it’s melting season. The National Snow and Ice Data Center released their Arctic sea ice update last week, and things don’t look good.

2007 saw a record ice minimum in September, which has left much of the Arctic with thin, year-old ice after this winter. (There are probably several reasons for 2007’s record melting, but a recent study found that an unusually sunny year is partly to blame.)

Although there is more ice in the Arctic than this time last year, the ice is melting 2300 square miles a day faster than a year ago. “Could the North Pole be ice free this melt season?” the NSIDC update asks.  “Given that this region is currently covered with first-year ice, that seems quite possible.”

Keep track of the updates here.

(Image: National Snow and Ice Data Center)