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New Report Outlines Great Lakes Climate Change Impacts on Agriculture

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  • Mike Neuman
    Farm & Market News New Report Outlines Great Lakes Climate Change Impacts on Agriculture Urbana , Illinois - Feb. 28, 2005 - There is growing evidence that
    Message 1 of 1 , Apr 6, 2005
      Farm & Market News
      "New Report Outlines Great Lakes Climate Change Impacts on

      Urbana , Illinois - Feb. 28, 2005 - There is growing evidence that
      suggests climate is changing in the Great Lakes region. Already
      winters are getting shorter, annual average temperatures are growing
      warmer, the duration of lake ice cover is decreasing as air and water
      temperatures rise, and heavy rainstorms are becoming more common.

      "There is an extensive amount of evidence indicating that the Earth's
      climate has warmed during the past century," said Donald Wuebbles,
      head, University of Illinois department of atmospheric
      sciences. "Foremost among this evidence are compilations of the
      variation in global mean sea surface temperature and in surface air
      temperature over land and sea."

      The increase in temperature has occurred in two distinct periods. The
      first was roughly from 1910 to 1945, and the second has been since

      "The 1990s has been the warmest decade on record. And recent state of
      the art numerical models from the National Center for Atmospheric
      Research suggest that natural variability of the climate is not
      sufficient to explain increasing temperatures," said Wuebbles.

      He says that by the end of the century, maximum daily temperatures
      could rise by 5 to l2 degrees in winter and 5 to 20 degrees in summer
      in the Great Lakes region. In addition, the growing season could be
      four to nine weeks longer.

      Precipitation While current analyses suggest that annual average
      precipitation may not change dramatically in the years ahead,
      seasonal precipitation in the region could become generally more
      extreme with less precipitation in the summer and more in the winter.

      "In the Midwest, changes in climate that have already occurred have
      produced longer growing seasons and heavier rainfall events," said
      Wuebbles. "And according to the latest models, average winter
      precipitation across the region will likely increase and summer
      precipitation will likely remain the same or decrease."

      However, by the end of the century, drought frequency will likely
      increase due to the combination of increased summer temperature,
      evaporation, and runoff from intense rainfall events, and a decline
      in summer precipitation.

      Overall, the region may grow drier because any increases in winter
      rain or snow are unlikely to compensate for the drying effects of
      increased evaporation and transpiration in a warmer climate.

      "This drying trend will affect surface and groundwater levels and
      soil moisture is projected to decrease by 30 percent in summer. In
      addition, the frequency of intense weather events such as 24-hour,
      multi-day downpours may increase flooding," said Wuebbles.

      The Causes Carbon dioxide is the largest changing concentration of
      the greenhouse gases and the one of most concern to scientists
      studying human effects on global climate.

      "Human activities are primarily responsible for the increase in
      carbon dioxide in the atmosphere," said Wuebbles. "Carbon dioxide has
      increased because of increased use of fossil fuel and because of land
      uses such as those related to deforestation and biomass burning."

      Wuebbles says that climate change has the potential to significantly
      affect agricultural, ecosystems, water resources, and human health
      and welfare.

      "All these areas are already under stress because of expanding
      population and continued urbanization. Climate change will further
      add to these stresses. Policies to address these potential impacts
      must be considered," he said.

      Impacts Expected for Crop Agriculture

      Together, the states of Illinois, Indiana, Michigan, Minnesota, Ohio,
      and Wisconsin have more than 380,000 farms, encompassing more than
      100 million acres of prime land with a total economic impact of $40

      Farmers in the region are already experiencing wetter spring and fall
      weather and more intense rainstorm events. These trends will continue.

      "Later in the century, the region's climate will grow considerably
      warmer and probably drier in the summer. By the end of the century,
      the region's climate will be quite different than it is today," said
      Michelle Wander, University of Illinois Associate Professor of soil

      Wander drafted the agricultural portion of the Union of Concerned
      Scientists publication Confronting Climate Change in the Great Lakes
      Region. The full report can be found at www.ucsusa.org/greatlakes/.

      "These changes will dramatically affect how the climate feels to us.
      By 2030, Illinois summers may resemble those of Oklahoma or Arkansas
      in terms of average temperature and rainfall. By the end of the
      century, however, the Illinois summer climate will generally resemble
      that of current east Texas. Winters will also change, albeit less
      drastically. By century's end, they may be warmer and drier, much
      like current-day Oklahoma," Wander projected.

      Yield Reducing Trends In general, using current climate comparisons,
      Great Lakes agriculture must prepare for climate conditions marked by
      extreme summer heat, summer drought, and spring and winter flooding.

      "Farmers in the region are already experiencing wetter spring and
      fall weather and more intense rainstorm events. In addition, farmers
      are challenged by changing technology and markets. These trends will
      continue and are likely strengthen," said Wander. Wander says that
      too much water at the wrong time leads to waterlogging and delayed
      planting. "On the other hand, four days of ill-timed soil moisture
      stress can reduce corn yields by 50 percent, and soil moisture stress
      already limits soybean yields."

      She says also that responses to moisture surpluses and deficiencies
      will increase production costs. Wet fall weather, for example, would
      increase the need for crop drying, and midsummer drought would
      increase the number of acres requiring irrigation. Such shifts will
      impose additional costs on farmers and increase tensions over limited

      Extreme events such as severe storms and floods during the planting
      season are likely to depress yields, too.

      "Soybeans are particularly vulnerable to climate variability.
      Perennial crops such as fruit trees and vineyards are also vulnerable
      because adjustments cannot be made as flexibly, putting long-term
      investments at risk. And the combination of flooding and high heat is
      especially lethal to both corn and soybeans," she said.

      Another factor in the climate change projections is an increase in
      atmospheric carbon dioxide.

      "Projections for soybeans, which are generally positive and
      attributed to both the CO2 fertilization effect and earlier planting
      dates, suggest increases in yield in the central and northern
      portions of the region but losses in southern areas. Soybean yield
      variability, however, is also expected to increase. Enhanced wheat
      yields of approximately 20 percent could result from these combined
      factors, but wheat production is likely to be limited by competition
      for land from other crops, including soybeans."

      However, these yield increases may be offset or negated by rising
      ozone concentrations that result from human activities such as the
      application of nitrogen fertilizers and burning fossil fuels.

      "Ozone is particularly damaging to soybeans and horticultural crops,
      and soybean yields in the region are already reduced approximately 25
      percent by ozone damage. But high heat and associated heat stress
      will also reduce corn yields in the south and western parts of the
      region," said Wander.

      Crop Pest Problems Climate changes will also affect the outlook for
      damaging crop pests.

      "Leaf-chewing insects and aphids are stimulated by elevated carbon
      dioxide. Higher temperatures, particularly in spring and summer,
      accelerate the number of generations of harmful multi-generational
      pests such as soybean and corn leaf aphids, potato leafhoppers, and
      two-spotted spider mites. Ranges for many pests, including bean leaf
      beetles and corn borer, have already expanded northward."

      Also, milder winters enhance survival for some pests such as bean
      leaf and corn flea beetles. A hot, dry summer may exacerbate yield
      losses from corn rootworm larvae. Excess moisture and humidity can
      increase the frequency of gray leaf spot, crazy top, and smut in
      corn; later in the century, drought will likely increase the damage
      inflicted by soybean cyst nematodes.

      On the other hand, extremes in temperatures and precipitation at
      important insect growth stages may reduce the threat of some pests
      such as western corn rootworm or European corn borer. The
      interactions of extreme weather events and insect reproduction,
      survival, and success are complex and must be evaluated on a species
      by species basis. Water Resources Agriculture's impact on the
      region's water resources is already a concern due to chemical
      contamination of ground and surface waters. As climate continues to
      change, these concerns will intensify.

      "More intensive production in the region's northern areas may require
      the use of more chemicals and nutrients. Increased flooding and more
      frequent extreme rainfall events will worsen soil erosion and
      introduce more agricultural chemicals and animal waste into the water
      supply," said Wander.

      She says that farmers' costs to maintain soil fertility and
      municipalities' costs to preserve or restore safe drinking water are
      likely to increase.

      "Eroded sediments and water runoff degrade streams and wetlands,
      reducing food and habitat for migratory birds and waterfowl. That, in
      turn, affects bird-watching and hunting activities, too."

      Policies Can Reduce Heat-Trapping Emissions The Environmental
      Protection Agency estimates that agricultural activities were
      responsible for nearly seven percent of total U.S. heat-trapping
      emissions in 2001. This estimate does not include carbon dioxide
      emissions from on-farm energy use, but does include methane and
      nitrous oxide emissions, which are also potent heat-trapping gases.
      The good news is that practical solutions exist today for agriculture
      to reduce these emissions.

      "Along with helping to address the growing problem of climate change,
      many of the solutions discussed below would also reduce soil erosion,
      improve air and water quality, increase biodiversity, and generate
      economic benefits," said Michelle Wander, University of Illinois
      Associate Professor of soil fertility.

      Wander and Steve Clemmer of the Union of Concerned Scientists
      collaborated to develop policy recommendations that would heat-
      trapping emissions. They recommend increased funding for energy
      efficiency and renewable-energy projects.

      "Over the past two years, the USDA has provided $44 million from the
      Farm Bill to support 280 renewable-energy and energy efficiency
      projects on American farms. Projects funded in the first year alone
      will produce enough electricity to supply the annual needs of 30,000
      households while creating 1,300 new jobs and reducing carbon dioxide
      emissions by more than one million metric tons over the life of these
      projects," said Clemmer.

      He notes, however, that the USDA has, in the past, denied proposals
      for dozens of other projects due largely to insufficient funding.
      Congress should increase funding levels, and states should offer
      incentives or tax credits to supplement these funds.

      Certain best practices in soil management such as no-till, reduced
      tillage, and crop diversification including the use of cover crops
      could enhance short-term soil carbon storage.

      "Effectively managed soils could abate an estimated 10 percent of
      heat-trapping missions produced in the United States over the next 30
      to 50 years. Additional funding should be made available from the
      USDA's Conservation Reserve Program, Natural Resources Conservation
      Service, and other programs to encourage such practices," said Wander.

      Wander recommends expanding programs to reduce nitrogen fertilizer

      "Best practices to achieve this goal could produce significant
      reductions in heat-trapping emissions while lowering nitrate
      contamination of water supplies," said Wander.

      For example, Wander says between 1985 and 1995, Iowa had several
      projects in place that reduced fertilizer use by more than two
      million tons, saved farmers $363 million, and reduced heat-trapping
      emissions by 10 million tons per year without affecting corn yields.

      Several states and the Environmental Protection Agency offer
      incentives and programs to reduce methane and nitrous oxide emissions
      from livestock and livestock waste.

      "For example, Haubenschild Farms, a 1,000-acre dairy farm in
      Minnesota, received state and federal assistance in 1999 to install a
      manure digester that converts methane into enough electricity to meet
      the needs of the farm and an additional 75 homes. The 750-head dairy
      generates nearly $81,000 per year from electricity sales and saves
      $4,000 per year in heating costs. These savings should recoup the
      initial $355,000 investment in five years or less," said Clemmer.

      Wander also recommends incentives to sequester carbon on marginal

      "Converting one million acres of marginal lands into native forests
      and planting 200,000 acres of riparian zone buffer strips with native
      trees or grasses such as switchgrass could reduce carbon dioxide
      emissions by an estimated 7.3 million tons per year. Additional
      funding should be made available from the USDA's Conservation Reserve
      Program, the U.S. Forest Service's Forest Legacy Program, and other
      programs," said Wander.

      It would also be wise to establish renewable energy standards for
      electricity and transportation.

      "Such standards are a popular and effective means of creating markets
      for clean energy produced on the farm. Standards requiring electric
      utilities to supply a portion of their electricity from renewable
      sources such as wind and bioenergy have already been established in
      18 states including Minnesota, New York, Pennsylvania, and
      Wisconsin," said Clemmer.

      He says a Union of Concerned Scientists study found that a national
      standard that would require utilities to provide 20 percent of their
      electricity from renewable sources by 2020 would create 355,000 new
      jobs including 30,000 in agriculture; save consumers $49 billion on
      their electricity and natural gas bills; and reduce the projected
      growth in power plant carbon dioxide emissions by 59 percent.

      Clemmer says competition from renewable energy would also lower
      natural gas prices, thereby lowering fertilizer prices.

      In Illinois, there is a growing interest in renewable energy sources.
      Governor Rod Blagojevich, in his 2005 State of the State Address,
      announced a goal for each electric utility to generate 8% of its
      electricity from renewable energy sources. The goal is to help create
      jobs, protect the environment, and promote energy independence.

      Source: Michelle Wander, 217-333-9471, mwander@...

      News writer: Gary Beaumont
      phone: 217-333-9440; email: beaumont@...

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