Sunday, January 3, 2010

Falling Water Tables Threaten Agricultural Production and Populations Around the World

Falling water tables around the world are threatening agricultural production and the livelihoods and well being of millions of people. Farmers are digging deeper wells, in some cases applying oil drilling techniques to reach water up to 400 meters below the surface. Farmers are also running larger electric water pumps around the clock, creating challenges in the power sector and increasing agricultural costs . In India, for example, power companies spend approximately $9 billion per year subsidizing power for irrigation, twice as much as the country spends on education. Examples include:
  • India - In North Gujaret, the water table is falling by 20 feet per year. In Tamil Nadu, the drying wells have reduced the amount of irrigated farm land by 50 percent in the last ten years.
  • Pakistan - In Rawalpindi and Islamabad, waters tables fell an average between 1 and 2 meters per year between 1982 and 2000. In Baluchistan, water tables are falling approximately 3.5 meters per year.
  • Iran - In the Chenaran Plain, in northeastern Iran, water tables were falling by 2.8 meters per year in the late 1990s.
  • United States - Water from the Ogallala aquifier, which stores water for Nebraska, Oklahoma and Texas, is being withdrawn between 130 and 160 percent above its replacement rate, leading to possibly being depleted within 40 years.
The critical concern over time is the continued overdraft of subsurface and surface water resources at the same time that increasing populations are creating greater demand on agriculatural production. Our global agricultural system is drawing upon water resources at rates that exceed the natural and sustainable replenishment rates. In rural areas of India, farmers are spending successively more resources to acquire water, by drilling deeper wells and running pumps longer. In some cases, towns are abandoning their wells, governments are trucking in water, and people are migrating away from water-poor locations.

More sustainable agricultural practices have to be adopted to reverse the accelerating depletion of available fresh water resources. Similar to the peak oil analysis done by Shell geologist M. King Hubbert in 1956, there is an explicit amount of fresh water resource available at any one time, governed by its natural replenishment rate. Unless we utilize water resources in a manner governed by natural replenishment rates, billions of people are at risk for the two most fundamental requirements for survival: food and water.

Saturday, January 2, 2010

Glacial Melting Threatening Populations Around the Globe

Glaciers around the world are disappearing on an accelerated basis, disrupting water flows upon which humans have depended for thousands of years. These climate driven changes are creating water shortages for entire populations, forcing governments to consider mass migrations in the interest of survival. In most cases, these aggressive reductions in water availability are occurring in places where the resources just do not exist to put adequate alternatives in place in time.

One place where this is occurring is Bolivia, where the existence of 100 million people in the region is threatened with the complete melting of most of the glaciers in the Andes within the next twenty years (according to the World Bank, as reported in the New York Times, December 14, 2009). In 2009, the Chacaltaya glacier, approximately 30 kilometers from La Paz, Bolivia disappeared. Water for La Paz comes from a cluster of nearby glaciers, which have lost 35 percent of their ice mass since 1983. Accordingly, the loss of Chacaltaya is the canary in the coal mine.

The first water migrations have begun, with people moving from Palca, which is in the mountains near La Paz, to El Alto, a fast growing municipality next to La Paz. Farmers and residents of mountainous villages such as Palca, have already begun to see glacial melt drying up in the summers, when water for their farms is crucial for survival. The next phase of water migrations are expected to drive people out of El Alto, where supply will fall below demand in just a few years, due to the combination of decreasing glacial runoff and increasing demand.

This same scenario is impacting peoples' lives in the Himalayas as well, with Himalayan glaciers having lost 21 percent of their glacial mass since 1962. Approximately 2 billion people in India, China and Pakistan depend on Himalayan glacial melt for irrigation and drinking water. With the first Himalayan glaciers expected to disappear by 2035, eventually significantly curtailing agricultural production, the disruption to millions of people's lives will be significant.

These real and current disruptions to people's lives around the globe, tied to massively disruptive climate change, provide a strong argument for significantly increasing the investment in clean energy technologies, and accelerating the deployment of increased efficiency and renewable energy throughout our economies.