Climate models help scientists understand global shifts in water availabilityNovember 17, 2005USGS scientists have a clearer picture of global shifts in water availability after examining a century of streamflow measurements from 165 locations around the world. Simulations from an ensemble of 12 global climate models compared favorably with the historical streamflow data. The scientists discovered that climate models have significant relevance in simulating historical long-term trends in streamflow around the world. That finding lends credibility to the same models' streamflow forecasts for the coming decades. And what do the models show about the future? The models predict 10 to 40 percent increases in runoff in eastern equatorial Africa, the La Plata basin and high latitude North America and Eurasia by the year 2050. They also predict 10 to 30 percent decreases in runoff in southern Africa, southern Europe, the Middle East and mid-latitude western North America by the year 2050. The article, "Global pattern of trends in streamflow and water availability in a changing climate," to be published tomorrow in the journal Nature, examines water-availability projections of climate models. The USGS scientists discovered that climate models are useful for simulating regional historical long-term trends in streamflow around the world. Lead author Christopher Milly explains the complex pattern of streamflow change by noting a basic fact of thermodynamics, "A warmer atmosphere can carry more water. So, warmer winds can deliver more water to a region, but they can also take more away. This give-and-take plays out differently in different parts of the world, causing decreases in water supply here, and increases there." Water availability is directly related to climate. However, there is no simple relationship for all regions between future temperatures and future water resources. Some regions may experience increases in precipitation and run-off while other regions may experience decreases. According to the study's authors, changes in sustainable water availability could have considerable regional-scale consequences for economies as well as ecosystems. Water availability on the continents is important for human health, economic activity, ecosystem function and geophysical processes. The USGS serves the nation by providing reliable scientific information to describe and understand the Earth; minimize loss of life and property from natural disasters; manage water, biological, energy, and mineral resources; and enhance and protect our quality of life. United States Geological Survey |
|||||||||||||||||||||
| Related Water Availability Current Events and Water Availability News Articles Water-conserving irrigation strategies minimize overwatering, runoff Conserving water and reducing the environmental impact of runoff are two of the most important issues confronting container nursery operations. Current regulations and laws in five states limit water consumption by container nurseries, and some states also limit nutrient concentrations in runoff. Growth versus global warming Houses on stilts, small scale energy generation and recycling our dishwater are just some of the measures that are being proposed to prepare our cities for the effects of global warming. Water scarcity will create global security concerns Water scarcity as a result of climate change will create far-reaching global security concerns, says Dr. Rajendra K. Pachauri, chair of the intergovernmental panel on climate change, a co-recipient of the 2007 Nobel Peace Prize. Water in a changing climate New research announced at the international Water in a changing climate science conference in Melbourne 24-28 August, implicates pollution from Asia, Europe and North America as a contributor to recent Australian rainfall changes. Satellites unlock secret to northern India's vanishing water Using NASA satellite data, scientists have found that groundwater levels in northern India have been declining by as much as one foot per year over the past decade. Researchers concluded the loss is almost entirely due to human activity. Bioethanol's impact on water supply 3 times higher than once thought At a time when water supplies are scarce in many areas of the United States, scientists in Minnesota are reporting that production of bioethanol - often regarded as the clean-burning energy source of the future - may consume up to three times more water than previously thought. Australia's top models at science conference Australia's top models will take centre stage in Cairns this week as scientists meet to discuss ways to understand climate change, improve air safety and enhance agricultural sustainability. Better water use could reduce future food crises If the overall water resources in river basins were acknowledged and managed better, future food crises could be significantly reduced, say researchers from Stockholm Resilience Centre at Stockholm University, Stockholm Environment Institute and Potsdam Institute for Climate Impact Research. Biofuels can provide viable, sustainable solution to reducing petroleum dependence An in-depth study by Sandia National Laboratories and General Motors Corp. has found that plant and forestry waste and dedicated energy crops could sustainably replace nearly a third of gasoline use by the year 2030. 'Deadly dozen' reports diseases worsened by climate change Health experts from the Wildlife Conservation Society today released a report that lists 12 pathogens that could spread into new regions as a result of climate change, with potential impacts to both human and wildlife health and global economies. More Water Availability Current Events and Water Availability News Articles |
|||||||||||||||||||||
|
|||||||||||||||||||||
|
|||||||||||||||||||||