Maine, New Hampshire, and Vermont all have received exceptional amounts of rain this summer, seriously damaging certain crops. Maine's raspberry and green bean crops were devastated, and livestock feed crops (grain and hay) could not be harvested due to the wet weather. Many farmers will be paying high prices to truck in feed to replace what was lost.

No particular weather event can be reliably ascribed to climate change. But as I talked to my farmer friend, I began to wonder if this summer's wet weather was a glimpse into the future for farmers in the region.

The IPCC predicts that regions that are already fairly wet will get even wetter over the next century. In the Northeastern U.S., precipitation is expected to increase by up to 5 percent in warmer months, and 10 percent in cooler months.

Precipitation in Maine this July was 25 percent above average, so even with the expected increase in precipitation most summers won't be quite as bad for farmers (and vacationers!) as this one. Still, the consequences of increased precipitation in the future may look quite similar to what Northeast farmers are experiencing now:

• Increased incidence of leaf and root pathogens is one of the worst problems with increased rainfall. Spread through the mold and fungus that thrive in the wet weather, these pathogens have had caused major damage to crops in Maine this summer. Wetter weather in the future is likely to cause similar problems.
• New weeds migrating northward with warmer weather are another problem Northeast farmers can expect to encounter, according to the U.S. Climate Change Science Program report.
• Traditional ways to control weeds won't work as well. The report goes on to say "recent research suggests that glyphosate, the most widely used herbicide in the United States, loses its efficacy on weeds grown at the increased CO₂ levels likely in the coming decades."

Net Plus or Net Minus?

Experts disagree on whether the overall impact of climate change on agriculture will be positive or negative. The impacts will vary from one region to the next. Higher levels of CO₂ and higher temperature may lead to increased plant growth and longer growing seasons in some areas. But even this may not be all good. Several studies have found that high levels of CO₂ can make food crops less nutritious.

Map created by Hugo Ahlenius, UNEP/GRID-Arendal.

Changes in precipitation patterns and the spread of new weeds, insects, and pathogens could severely reduce yields. The Northeast is likely to experience wetter weather, and I've mentioned the problems this can cause. Other regions of the country – areas that produce higher volumes of crops – may experience increased drought, or more frequent and extreme rainfall events.

The IPCC predicts that, overall, climate change will cause a 5 to 10 percent increase in aggregate yields from non-irrigated agriculture. However, the report from the U.S. Climate Change Science Program predicts that productivity increases will only be short term:

[O]ver the long term, many such systems are likely to experience overall decreases in productivity that could result in economic losses, diminished ecosystem services, and the need for new, and in many cases significant, changes to management regimes.

One thing seems clear: farmers across the U.S. and around the world will have to cope with more unpredictable and extreme weather as the Earth warms.

This post is by Britt Lundgren, an agricultural policy specialist at Environmental Defense Fund.

Two weeks ago, Lisa Moore posted about a dangerous suggestion from Congress and producer groups to allow the penalty-free release of up to 24 million acres from the Conservation Reserve Program so the land could be put back into crop production.

Yesterday, U.S. Agriculture Secretary Ed Schafer decided again it. Good call! From Sara Hopper, EDF's director of agricultural policy:

Secretary Schafer should be commended for resisting calls to gut the nation’s oldest and most successful farm conservation program. Putting millions of CRP acres back into intensive crop production would have resulted in the loss of billions of dollars in taxpayer investments in conservation and caused untold environmental damage, while only minimally boosting crop production and providing little, if any, relief from rising commodity prices.

Congress and producer groups are pressuring the U.S. Department of Agriculture (USDA) to release millions of acres from Conservation Reserve Program (CRP) contracts and open them up to crop production. Supporters say this move would increase production and bring down food prices.

Wrong! Ripping up conservation lands would not make a big dent in commodity supplies or prices, but it would waste billions of taxpayer dollars that have been invested in conservation on these lands.

It also would be a tragedy for wildlife, water quality, and climate.

There are approximately 35 million acres protected under CRP, about the size of the state of Iowa. The program rewards farmers who take land out of production and use it to restore valuable ecosystems. Landowners who back out of their contracts early must reimburse the government for the payments they have already received, and pay an additional penalty.

Now the USDA is considering waiving these costs for up to 24 million acres, allowing farmers to bail out early on their contracts and plant row crops on this land.

As croplands, these fragile areas are marginal at best, and typically have yields that are half what you could get on good cropland. Why do you think they were taken out of production in the first place?

But as restored wetlands, forests, and grasslands, they are tremendously valuable. They decrease erosion, improve water quality, store carbon, and provide critical habitat for declining grassland birds and waterfowl. In fact, the CRP is sometimes called a "duck factory".

Ripping up CRP land to plant row crops would have devastating effects:

• Expose tons of soil to wash or blow away
• Increase greenhouse gas emissions
• Destroy valuable wildlife habitat
• Potentially worsen future flooding

Last week, 15 conservation groups, led by Environmental Defense Fund, sent a letter to the Secretary of Agriculture, urging him to protect this critical conservation program. Let's hope he does the right thing.

Thanks to Britt Lundgren, agriculture policy expert at EDF, for her input into this article.

Last month I posted about the gridlock over the 2008 Farm Bill, and discussed how different programs in the Farm Bill might impact global warming. The conference report (final version of the bill) has now been issued, and Congress is scheduled to vote on it today.

How did it turn out? The final bill includes important new investments in conservation, but doesn't do enough to expand and improve conservation programs, or reform our antiquated system of farm subsidies.

Here are the details.

Some Funding for Conservation

The bill includes $4 billion in new funding for the U.S. Department of Agriculture's voluntary conservation incentives programs, and $1 billion in new funding for renewable energy programs.

Conservation Incentive Programs

• The Environmental Quality Incentives Program and the Conservation Security Program provide incentives for farmers to switch to low-carbon farming practices such as conservation tillage.

  Funding for both of these programs is increased.

• The Conservation Reserve Program provides financial and technical assistance to farmers who take environmentally sensitive lands out of production, and restore them by planting native grasses or trees. This sequesters carbon as well as restoring wildlife habitat.

  Enrollment in this program is reduced to 32 million acres. The current cap is 39 million acres, with actual enrollment of about 36 million acres.

Renewable Energy Programs

• The 9006 program – renamed the Rural Energy for America Program – shares the cost of conducting an energy audit on a farm or installing renewable energy technology – for example, methane biodigesters, windmills, or solar panels.

  This program got new funding.

• A new program – called the Biomass Energy Reserve in the House bill and the Biomass Crop Transition Assistance Program in the Senate bill – fosters bioenergy technology through incentives for planting new cellulosic feedstocks.

  This program, now called Biomass Crop Assistance Program, received new funding.

A Disastrous One-Two Punch

Both the House and Senate versions of the bill included a Sodsaver provision that would have barred crop insurance, and withheld some disaster payments to producers who plowed native grasslands to plant crops. But conference committee members gutted this provision during meetings that were not open to the public.

At the same time, the conference committee added almost $4 billion in new subsidies for a Permanent Disaster Fund. This is a real disaster for the nation's remaining native prairies; it will accelerate the conversion of grassland to intensive crop production.

In a report issued last fall [PDF], the Government Accountability Office found that loss of grasslands – more than 25 million acres since 1982 – has been driven by the availability of crop insurance, disaster payments, and other farm subsidies.

Together, Sodsaver and the Permanent Disaster Fund are a one-two punch against conservation of native prairie, and carbon sequestration by grasslands. Add to this the pressure on grasslands from high crop prices and you have a perfect storm for environmental destruction on the Great Plains.

President Bush has already promised to veto this bill. If he follows through on this threat, we'd like to see prompt action by Congress to send the bill back with at least as much money for conservation programs, a strong Sodsaver provision, and meaningful reforms of farm subsidies.

Late news: The House just voted to pass the bill 318 to 106 – a veto proof margin. The Senate vote will be tomorrow.

Want to know how your lifestyle impacts the environment? Yahoo Green's Lifestyle Calculator (data provided by EDF) estimates your carbon footprint based on factors like the size of your home, and how much you drive and fly. The H₂O Conserve Water Use Calculator asks questions about your habits to assess your water usage (see why saving water saves energy)

But what about the food you eat? Bon Appétit Management Company has a new Low Carbon Diet Calculator that can tell you. It has a very entertaining interface, but how good is it? We asked Lisa Moore, Ph.D., a scientist at Environmental Defense Fund, to check it out.

Lisa found no glaring errors, but she noted two caveats:

• The calculator is specific to Bon Appétit's recipes, cooking
  processes, and supply chain.
• Most of the numbers are underestimates (for example, it doesn't include emissions from all recipe ingredients, and it omits nitrous oxide emissions from fertilizer use).

Still, the calculator can give you a sense of which foods have higher emissions than others. For example, it says that beef has higher emissions than pork, pork more than chicken, and chicken more than vegetables. This is the same order as our own analysis, but the magnitudes are different.

Bottom line: The calculator is good for comparisons, but not exact numbers.

The New York Times recently reported that thousands of farmers are dropping out of the federal government's Conservation Reserve Program. The prices for corn and other crops are so high that conservation subsidies can't compete with what farmers can make by planting the land. One reason for the high prices is the ethanol mandate in the energy bill Congress passed last year.

Shifts in land use from diverting food-producing land to grow crops for energy – called "indirect land-use change" – can potentially negate the environmental benefits of corn ethanol. There is still much debate on how to measure it, but no question it's important to consider. One recent study published in Science (Searchinger et. al.) found that using croplands for biofuels causes a significant increase in greenhouse gas emissions relative to gasoline when indirect land use change is taken into account.

Unintended consequences such as these highlight the danger of mandating a specific clean energy technology, and the importance of relying on performance standards instead.

What is "Indirect Land Use Change"?

When food-producing land is diverted for energy production, the food that would have been grown on that land must be grown elsewhere. This prompts farmers to convert land not currently in production into cropland. When grassland or forestland is cleared to grow crops, the carbon sequestered in the soil and trees is released into the atmosphere.

If a lot of new land is cultivated, the resulting carbon release can completely negate the benefits of using biofuels. The New York Times said as many acres as in Rhode Island and Delaware combined were removed from the Conservation Reserve Program, and that's just one corner of the country. Not all the land was removed due to U.S. biofuel policy, but it plays a part. Some research has found that U.S. policies can contribute to deforestation in southeast Asia and the Amazon.

Assessing the impact of indirect land-use change is tricky, and experts disagree on how to quantify it. According to the Searchinger study, when indirect land-use change is factored in:

• Corn ethanol nearly doubles greenhouse gas emissions relative to gasoline when considered over a period of 30 years, and emissions remain elevated for 167 years.
• Even biofuels from switchgrass, if grown on U.S. corn lands, increase emissions relative to gasoline by 50 percent.

We can't say whether these numbers are exactly correct, but we can say that indirect land use effects – particularly tropical deforestation – are important to consider.

Shaping Policy to Reduce Emissions

Government mandates for a specific technology to lower greenhouse gas emissions risk unintended consequences – even higher net emissions.

An effective policy that ensures lower emissions has two key components:

• A market-based system that rewards less carbon-intensive technologies and land-use practices, whatever they may be.

  The Searchinger study suggests that a possible solution to the corn ethanol problem is to use waste products as a "feedstock" (raw material to produce biofuels). Unlike cultivated crops, waste products don't compete for agricultural land and drive up commodity prices. Sustainably produced cellulosic ethanol made from grasses and wood also may be a viable alternative. Another possibility we'll discuss in an upcoming post is using algae to make ethanol. But a policy that specifically mandates corn ethanol doesn't encourage exploration of these other options.

• Performance standards based on full lifecycle analysis, including emissions from tropical deforestation and other indirect land use changes.

  There is some recognition of this in current policy, but also an important gap. The California Air Resources Board (CARB) Low-Carbon Fuel Standard and Environmental Protection Agency (EPA) Renewable Fuel Standard (RFS) both require consideration of indirect land use in assessing emissions. But the EPA's RFS exempts corn ethanol from existing facilities from having to meet lifecycle emissions standards.

Biofuels may have a role in our energy future, but only if they're produced in ways that lower emissions. Performance-based standards and market incentives can prevent the unintended consequences of mandating the wrong technology.

You may have heard about the gridlock over the 2008 Farm Bill, which was supposed to have been signed into law already, but hasn't yet. Versions of the bill have passed both the House and the Senate. Now the bill is "in conference" to resolve differences over new spending and offsets to pay for the bill.

It's unclear whether the conference will produce a bill that the President will sign. The President has repeatedly threatened a veto, saying he wants more reform of our antiquated system of crop subsidies (a point on which we strongly concur – see my guest post on Grist).

Still, there is much we stand to lose if Congress and the President can't agree on a good a new Farm Bill. The 2008 bill includes significant new funding for the U.S. Department of Agriculture's voluntary conservation incentives programs and renewable energy programs.

Farming affects global warming because of "biological sequestration". As plants grow, they remove carbon dioxide (CO₂) from the air and store the carbon in leaves, stems, roots, and soil. Plowing the soil and clearing forestland to plant crops releases CO₂ back into the atmosphere where it can trap heat and cause global warming (the "greenhouse effect").

Voluntary Conservation Programs

The Farm Bill's voluntary conservation programs encourage farmers to implement practices that sequester more carbon in the soil. For example:

• The Environmental Quality Incentives Program and the Conservation Security Program provide incentives for farmers to switch to low-carbon farming practices such as conservation tillage.
• The Conservation Reserve Program provides financial and technical assistance to farmers who take environmentally sensitive lands out of production, and restore them by planting native grasses or trees. This sequesters carbon as well as restoring wildlife habitat.

But all the conservation programs are woefully underfunded. Without additional funding from the 2008 Farm Bill, two-thirds of farmers who apply to participate will continue to be turned away.

Renewable Energy Programs

The Energy Title of the Farm Bill also contains several programs that help farmers reduce their impact on global warming.

• The 9006 program – renamed the Rural Energy for America Program – shares the cost of conducting an energy audit on a farm or installing renewable energy technology – for example, methane biodigesters, windmills, or solar panels.
• Another new program – called the Biomass Energy Reserve in the House bill and the Biomass Crop Transition Assistance Program in the Senate bill – fosters bioenergy technology through incentives for planting new cellulosic feedstocks.

Without these new Farm Bill provisions, most farmers who want to install a windmill or a methane biodigester, or experiment with planting crops for cellulosic biofuels, will have to do so on their own. Banks are often unwilling to provide loans for farmers to install these technologies, making it extremely difficult for farmers to do this without federal assistance.

A Mixed Bag

The 2008 Farm Bill certainly isn't the answer climate change. Some crop subsidy programs may exacerbate global warming by encouraging farmers to bring new lands, such as native grasslands, into crop production. This destroys ecosystems and releases CO₂.

But the voluntary conservation and energy programs funded by the Farm Bill are important tools for farmers wanting to reduce their impact on the climate. Also, these programs can prepare farmers to participate in the carbon market that will be created with national climate legislation.

Everyone can do something to help stop global warming. Here's an example…

When California passed the Global Warming Solutions Act (AB 32), California rice growers wanted to explore ways to lower their net emissions. But exactly how to go about doing this wasn't clear, so Environmental Defense teamed up with the California Rice Commission to work on the challenge.

As in other sectors of agriculture, rice farms both produce greenhouse gas emissions (mainly in the form of methane) and sequester carbon in field vegetation and soils. Our two-year project, launched in October, seeks to develop precise techniques – voluntarily implemented – to reduce emissions and increase sequestration, and to quantify emission benefits.

Our goal is to develop a comprehensive menu of options for rice growers wishing to reduce their greenhouse gas footprint. The technologies we identify, refine, and develop will be field tested on participating rice farms in California's Sacramento Valley.

These carefully quantified voluntary practices have the potential to be sold as carbon offsets. Participating growers who implement these techniques could earn offset credit. To better understand this potential, we will work with a small group of rice growers to develop greenhouse gas offset trading opportunities. This will allow us to evaluate the level of incentive necessary to make an offset market attractive to growers.

We're really pleased to be working with the California Rice Commission on this project. Our technical team, which includes researchers from the University of California, Davis; University of New Hampshire; and Applied Geosolutions, Inc., are currently refining and calibrating the computer model that will be used to calculate greenhouse gas emissions and emission reductions.

We hope to have the computer model up and running by the spring planting season so that we can launch on-the-ground trials in 2008. Stay tuned to Climate 411 for periodic updates.

1. Increased CO₂ and Food Quality
2. Farm Animals and Methane
3. "Food Mile" Complexities

The author of today's post, Sheryl Canter, is an Online Writer and Editorial Manager at Environmental Defense.

When it's apple season here in New York and the green markets are overflowing, for a store to ship in apples from Washington State or New Zealand burns fuel for no good reason. Local food is fresher, tastes better, and supports the community. And locally produced food often results in lower greenhouse gas emissions – but not always. The greenhouse gas calculation is complicated, and you can't assume that if a crop is produced locally, greenhouse gas emissions are lower.

For starters, the term "food mile" is itself problematic. A mile travelled by a large truck full of groceries is not the same as a mile travelled by a mini-van carrying a crate of carrots. A report published by DEFRA [PDF], Britain's environment and farming ministry, says it's more useful to think in terms of "food-vehicle miles" (the miles travelled by vehicles carrying food) and food-tonne miles (which considers the tonnage being carried).

The DEFRA report contains several counterintuitive findings:

• Trucking in tomatoes from Spain during the winter produces less greenhouse gas emissions than growing them in heated greenhouses in Britain.
• A shift towards local food systems might actually increase the number of food-vehicle miles travelled. This is because supermarket-based food systems have central distribution depots, short supply chains, and big full trucks. In local food systems, food is distributed in a larger number of smaller, less efficiently packed vehicles.

But the DEFRA report is not the last word on the subject. The Leopold Center for Sustainable Agriculture found different results in its 2001 study "Food, Fuel and Freeways". They reported that conventional food systems used 4 to 17 times more fuel and emitted 5 to 17 times more CO₂ than local and regional food systems, depending on the system and truck type.

A Lincoln University study [PDF] included elements they called "factor inputs and externalities" in analyzing the impact of food miles – for example, the amount of water and fertilizer used, harvesting and storage techniques, means of transport, and dozens of other aspects of cultivation. They found that lamb raised on New Zealand's lush pastures and shipped 11,000 miles by boat to Britain produced 1,520 pounds of CO₂ per ton, while British lamb produced 6,280 pounds. The reason? British pastures provide poorer grazing, forcing farmers to use feed. They found similar results for dairy products and fruit.

There's a push for "food miles" labeling in both the U.S. and Europe. North Carolina State University's Center for Environmental Farming Systems is working with FoodLogiQ to develop a pilot program in North Carolina with an eye towards national implementation. Local food is fresher and supports the community, so a locale label can tell you that much. But "local" doesn't necessarily mean lower greenhouse gas emissions. That depends largely on how the food is produced and transported. Just knowing where the food was produced doesn't tell you that.

1. Increased CO₂ and Food Quality
2. Farm Animals and Methane
3. "Food Mile" Complexities

For the second course in our food series, let's start with some pie – specifically, Bill's greenhouse gas pie showing the contribution of different greenhouses gases to global warming. The first chart shows that methane is the second largest contributor to global warming.

Globally, nearly half of that hefty methane slice comes from agriculture. What causes these emissions, and how can we reduce them?

The main source of agricultural methane is a process called enteric fermentation, a normal part of digestion in ruminant animals such as cows, sheep, goats, buffaloes and camels. Ruminants have a compartment in their stomach called a rumen where food is broken down through fermentation. This process produces methane gas, which the animals then belch out into the atmosphere. Enteric fermentation accounts for 18 percent of all anthropogenic methane emissions.

If enteric fermentation is a natural part of ruminant digestion, then what's the solution? One strategy is to adjust the feed mix. The harder a food is to digest, the more time it spends in the rumen and the more methane that is produced. Some supplements can help as well. A recent study in Wales found that garlic may cut methane emissions.

The other major source of methane from farm animals is manure – particularly when stored in uncovered tanks or lagoons. Cow paddies sprinkled across a field of grass are exposed to the air where they quickly dry out. In tanks and lagoons (used because feedlots contain so many animals), lack of oxygen increases the amount of methane that's emitted.

One way to handle the problem is through anaerobic digestion of manure stored in closed vessels. The captured methane can be used to generate heat and electricity. The 7,000+ dairy and swine operations in the U.S. could generate enough electricity to power nearly 600,000 homes annually, preventing the release of 1.3 million tons of methane into the atmosphere (see EPA report [PDF]). As an added benefit, the digested manure can be used as a fertilizer. (Raw manure also is used as fertilizer, but has a much stronger odor.) Since producing synthetic fertilizer burns a lot of fossil fuel energy, fertilizing with manure is a way to reduce greenhouse gas emissions as well as save money.

There are challenges with anaerobic digesters. Odors can be a problem if the digester effluent isn't stored and managed properly. Also, as this Cornell University presentation [PDF] points out, you must have enough land to absorb all that fertilizer – or a plan to export it if you don't. Anaerobic digestion can be used in concert with other manure management techniques, such as solid-liquid separation and composting.

Livestock production contributes to global warming – no question about it. But fortunately, there are steps that farmers and ranchers can take to decrease methane emissions while potentially increasing profits.