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Drought and Flood Effects

It is a tale of too much and too little right now in the Northern Hemisphere.  Communities are suffering weather-induced miseries.  Crop production is way off, and the future of food production in the region is looking worse.  Ecosystems are under stress and so too the animals that depend on them.  Experts are unable to forecast just when there might be some relief from these extreme conditions.  In California, it is a tale of searing drought.  In the United Kingdom, it is a tale of relentless rain and wind, and incursions from the sea.GRACE_SFSM

In the United Kingdom, the coastal communities that were hard hit with flooding and other damage by record storm surge and rainfall in December continue to be battered by the elements (read more here).  In 2012, the country experienced only nine severe flood warnings.  Since December, there have been 130 such warnings, which indicate the potential for loss of human life, according to the BBC. The flooding has spread inland.  The country’s emphasis on creating or protecting more wetland areas for biodiversity and other services appears to have been at the expense of ensuring that additional building did not occur in vulnerable areas.  While wetlands perform a critical role in managing floodwaters, they cannot provide unlimited absorption and filtration services.  How government funds are allocated in preparing for floods can improve or undermine those services.

In a recent London Guardian article, concerns were expressed on all sides that putting flood response personnel on 24/7 alert while asking the responsible agencies to cut their budgets 13% was not the solution to preparing the country for the effects of climate change.  It is anticipated that some 30,000 hectares (approximately 74,000 acres) will be flooded at least once every three years in the decades to come, according to a study cited in the article.  As an island nation, the United Kingdom is accustomed to importing food, but homegrown crops have always provided an important part of the nation’s security.

20140204_west_trdCrop production is at risk in an entirely different way in California’s Central Valley and across the drought-stricken region where a third year of drought threatens the economy, environment, and community well-being of the state.  For precious freshwater, time is allocated differently—the “water year” begins October 1 for planning purposes—timed to start with the fall and winter rains, when they come.  Some experts believe that this water year will be the driest since the early 1920’s.  As the water flow from three great river systems (the Sacramento, the San Joaquin, and the Tule Lake basin) slows or disappears, the Central Valley Aquifer is not recharged and withdrawal pressure on the resource grows.  As groundwater levels drop, so too does the land above it—creating buckled sidewalks and fissures in the land.

In 2012, California’s 80,000 farmers and ranchers earned some $44 billion for producing an array of products that include the twelve top crops: milk, hay, corn, tomatoes, grapes, almonds, livestock, lettuce, walnuts, strawberries, and nursery plants. Some $19 billion in food exports derive from California alone—an important component of the importing countries’ food security as well.  Yet, not only is that productivity being challenged—dozens of rural communities are at risk of running out of water before Memorial Day.  State officials are confronted with a major challenge:  How to maintain that productivity and the state’s overall economic health without adversely affecting the ability of the aquifer to recharge, and assuring that other water needs of the state’s human and other natural resources are met.

How do we know how fast the aquifer levels are dropping? Because of NASA’s Grace (Gravity Recovery and Climate Experiment), which is a pair of twin orbiting satellites that can detect small changes in gravitational fields on the earth’s surface that represent changes in groundwater levels in the aquifers below.  Since 2002, NASA and its international partners have used Grace to help water experts around the globe understand where the greatest threats to freshwater supply lie—from the aquifers of Iraq and other parts of the Mideast to the one in California’s Central Valley.  Grace has helped confirm the patterns that the northern latitudes and tropics are getting wetter and the mid-latitudes are getting drier.

So, what does it mean for the natural resources of our communities when this kind of extreme inundation and extreme drought occur?  It means that human infrastructure may have to move and change which may mean increased human activity in areas that were not so affected before.  It means that species that cannot adapt to the shifts in precipitation patterns are at great risk, both migratory and stationary species.  And it means that greater conflicts arise among human uses—whether it is for food production, drinking water, or, increasingly, energy extraction—and between those and the needs of natural ecosystems and the plants and animals that are also dependent on those systems.  Extreme weather affects the food security of all living beings.

It means that we have to avoid the kinds of “fish versus people” (Sacramento Delta) or “birds versus people” (United Kingdom) arguments that inevitably surface when dealing with water and habitat management.  It is recognition that birds, fish and other wildlife resources are part of our collective well-being, and offer their own economic and other benefits to human communities as well.  It is recognition that stewardship of resources is challenging but cannot be wholly viewed through the lens of today’s people needs first.

It means that we have to be sure that Grace is replaced when she ages past her useful life in a year or two.  It means we have to monitor the populations of the salmon runs and assure that we are meeting at least the minimum scientific recommendations for water flow and quality—if the salmon cannot spawn for several years, the populations are gone.  It means that we have to monitor migration patterns and understand where populations of migratory birds, marine mammals, and other species are going if they are not passing through California.  It means we have to understand that the hard choices of reducing livestock herds and crop acreage may reverberate through the economy, increasing food prices and reducing demand for agricultural machinery and other infrastructure.  In turn, that economic hardship will affect government budgets for addressing food security and natural resource management.

Comments

  1. Nancy Vollmar
    Bichanan Dam,Texas
    February 20, 9:29 pm

    In the hill country in lTexas we are yin diar circumstances. Buchanan Dam is a feeder lake for electrical power and water for the Hill Country as well as Austin area. We are desperate as the lake continues to decrease and the aquifer in on decline.

  2. Rick McGivern
    Columbus Ohio
    February 14, 12:26 pm

    While global warming may be causing environmental damage, there are projects on the drawing board to redistribute water to California and other drought-impacted states and mitigate much of the damage. Join the ‘GRAND Canal’ group on LinkedIn to learn more