NASA Expands its Exploration of Planet Earth

An unusual March snow storm here in Virginia has me obsessing on weather. The Global Precipitation Measurement (GPM) Core Observatory satellite, a joint mission between NASA and the Japan Aerospace Exploration Agency (JAXA), was launched into space at 3:37 a.m. Japanese Standard Time Friday, February 28, 2014  from Tanegashima Space Center in southern Japan.

The Global Precipitation Measurement (GPM) mission is an international partnership led by NASA and the Japan Aerospace Exploration Agency (JAXA). The mission centers on the GPM Core Observatory satellite. This satellite is now 253 miles above earth traveling at 4.3 miles a second in a circular non-sun-synchronous orbit. The GPM satellite will make 16 orbits a day carrying two instruments: the GPM Microwave Imager and the (GMI) and Dual-frequency Precipitation Radar (DPR), an advanced radar/radiometer system that can measure the amount, size, intensity and type of precipitation, from heavy-to-moderate rain to light rain and snowfall. The DPR will return three-dimensional images of precipitation, revealing the internal structure of storms within and below clouds. The Microwave Imager will serve as a calibration tool.

The GPM mission builds on the success of the Tropical Rainfall Measuring Mission (TRMM), a joint NASA and JAXA satellite launched in 1997 that measures precipitation over tropical and subtropical regions of the earth. During World War II scientists developed the ability to use ground-based radar to measure precipitation over land. The TRMM was the first utilization of spaceborn precipitation radar and this has resulted in the advances we’ve seen in the last 20 year in tropical storm monitoring and forecasting.

With its higher orbit and more advanced instruments the GPM Core Observatory satellite will provide even greater coverage of the earth-from the Arctic Circle to Antarctica. GPM Core Observatory will carry the next generation precipitation radar, the Duel-frequency Precipitation Radar (DPR). One of the major advancements of the DPR is the second radar frequency. In addition to the DPR’s Ku-band radar that will measure moderate-to-heavy rain at 13.6 gigahertz, its Ka-band radar will measure frozen precipitation and light rain at 35.5 gigahertz. These measurements, combined with those from other satellites in the constellation, will provide global precipitation observations approximately every three hours.

Measurements from the GMI will also serve as a reference standard for cross-calibration of the other satellites in the GPM constellation that have sensors to provide data. You can read about the transfer of and coordination of all the satellite data in the NASA mission brochure.

The calibrated GPM constellation will provide measurements on the:
• Intensity and variability of precipitation;
• Structure of cloud and storm systems;
• Microphysics of the ice and liquid particles within clouds; and
• Amount of water falling to Earth’s surface.

Observations from the GPM constellation, combined with land-surface data, will improve our knowledge and understanding of our planet’s allowing for the creation of better:
• Weather forecast models;
• Climate models;
• integrated hydrologic models of watersheds; and
• Forecasts of hurricanes, landslides, floods and droughts.

Rainfall and snowfall vary greatly from place to place and over time as weather and climates change. Satellites can provide more uniform observations of rain and snow around the globe than ground instruments, especially in areas where surface measurements are difficult to take, for example over the oceans and in extreme altitudes. The GPM mission will help scientists understand how local, regional and global precipitation patterns change over time. The GPM Core Observatory satellite is designed to serve for 3 years and carries 5 years of fuel.

The distribution of water in the atmosphere and how it moves, changing between its solid, liquid and gaseous forms, is a powerful vehicle for redistributing Earth’s energy and influences the behavior of the planet’s weather, climate and other environmental systems. Lack of full data and understanding of the water cycle has hindered the ability of scientists to develop accurate models to forecast weather and climate. We cannot predict weather accurately more than a few days out and all the climate models have failed to demonstrate any ability to forecast the future. Now, there is hope of using the collected data to develop a better understanding of our planet and to ultimately build predictive models of our weather and climate. Mission Video

Farm Exports- Selling Our Water and Future to China

Paradise, CA

According to the US Census Bureau there are 312 million people in the United States. As population rises, the demand for fresh water for drinking, domestic use, for industry (especially power generation) and for agriculture increases. The demand for food and the water that is essential to produce food grows with population and wealth. Globally, farming is estimated to account for 92% of water footprint of mankind. Farmers in the United States feed 20% of the world’s population on just 10% of the earth’s surface which has resulted in the United States being the largest virtual water exporter on the globe.

Though “on average” the United States actively uses less than 8% of the water that falls as precipitation within our borders annually, the rain and snow does not fall where needed and when it is needed, our groundwater aquifers are necessary to maintain year round water and supplement surface water supplies. However, we are depleting key aquifers in the United States. In the High Plains that was open range land until the groundwater from the Ogallala aquifer was used to turn the range land into irrigated crops, agriculture is depleting the aquifer because the groundwater within it is predominately non-renewable. In the central valley of California where three crops a year can be grown and crop production is only limited by the amount of water delivered for irrigation, the groundwater is used to increase irrigation waters making up an estimated of 30% of water for irrigation from an aquifer that is also predominately non-renewable. So much water has been pumped that the land above the aquifer- the fine-grained confining beds of sediments- that the land has subsided and can never recover. The water level in both these aquifers has fallen hundreds of feet in the past few generations.  

This year it is estimated that the Western United States will ship more than 3.6 million tons of hay and alfalfa whose water footprint is more than 50 billion gallons of water to China this year. We do this in a drought year when the limited water of the Colorado River could be better used elsewhere in the United States and by consuming non-renewable groundwater. Farmers pay almost nothing for water- only what it costs to deliver it, not what it is worth. So, for less than $180 American farmers are selling 13,900 gallons of water to China. This water is both the limited flow of the Colorado and non-renewable groundwater resources.  

In many parts of the United States, water resources are limited and strained. Without irrigation even a single crop is impossible with less than 20 inches of rainfall. Yet, we still behave as if water were unlimited and almost free. Irrigated agricultural consumes over 75% or more of the delivered water in California, which produces about half of U.S. grown fruits, nuts, and vegetables. In the United States we have used the various complicated, layered and hidden subsidies within the various water rights arrangements and subsidized water to complicate the business of farming and obscure the true costs of food in America and now we are consuming our non-renewable water resources and subsidizing the water cost for hay and nuts for China. The basic laws and regulations governing water and water rights have not been updated to account for today’s water realities and for recent advances in scientific and technical understanding of the relationship between water, groundwater and ecological services that water perform.

The system of water rights that developed in the west assured for generations the allocation of water to agriculture. The water rights system as conceived and administered in the western states was not designed to conserve water. It was developed in a time when population was still sparse, water supplies were believed to be more than plentiful and development and growth were to be encouraged. The system was designed to protect the water and work necessary to build farms in the west and the government actually encouraged the conversion of over 91% of the range land into cultivated agriculture. This management scheme has resulted in non-sustainable use of groundwater and unsustainable agricultural practices. We are draining the High Plains Aquifer and the Central Valley aquifers though agricultural crop volume per gallon of water has increased over the past generation by adopting more efficient irrigation technologies.

The states of the Colorado Compact need more water. The allocations promised under the Compact were more than 100% of the water available , and the water needs of the states have grown over the years. The water allocated under the Colorado Compact was based on an expectation that the river's average flow was 16.4 million acre feet per year. According to the University of Arizona, a better estimate would have been 13.2 million acre feet at the time of the Colorado Compact and there are indications of periods of mega-droughts in the distant past. During the drought of 2001-2006 the Colorado River flow was estimated at 11 million acre feet and hit a low of 6 million acre feet in 2002.  Overuse is killing the Colorado water basin which suffers from decimated aquatic ecosystems, overdrawn and irreparably damaged groundwater aquifers, and polluted agricultural and urban runoff.

California farmers have nontransferable water rights to 20% of the flow of the Colorado River exceeding by an order of magnitude the rights of the state of Nevada. Even with such a large share of the Colorado’s flow California has failed to develop a sustainable water budget. There is little incentive for farmers with senior rights to fully implement water saving strategies- the water is priced too cheap and farmers are unable to sell water rights. By prior appropriation water rights belong to the agricultural irrigation districts despite the changing needs of our nation and a changing understanding of water. The states of the Colorado Compact, the states of the High Plains, and the other major watersheds need to rationalize our water policies and create a sustainable and workable water budget for their communities and our nation as a whole and stop exporting the non-renewable water resources as cheap grains and hay.  

Water, Water Everywhere, How Much is there to Drink?

All the water that ever was or will be on earth is here right now. More than 97% of the Earth’s water is within the in oceans. The remaining 2.8% is the water within the land masses. The land masses contain all the fresh water on the planet. Of the land surface water, 77% is contained in icecaps and glaciers and for all practical purposes is inaccessible in the short run. The remaining fresh water is stored primarily in the subsurface as ground water with a tiny fraction of a percent of water is stored as rivers and lakes.

The water on earth never rests, it is constantly moving within the hydrologic cycle along various complex pathways and over a wide variety of time scales. Water moves quickly through some pathways -rain falling in summer may return to the atmosphere in a matter of hours or days by evaporation. Water may travel through other pathways for years, decades, centuries, or more—the groundwater stored in the Wasia aquifer in Saudi Arabia fell from the atmosphere as rain thousands of years ago.

Water enters the atmosphere through evaporation and exits as precipitation -rain or snow. Typically, water remains in the atmosphere as vapor for about 10 days and it is this time that allows water to move from the oceans to the land mass. Then condenses and becomes rain, snow, or mist. The pattern of precipitation changes over time and causing or responding to changes in the climate of the planet. A falling raindrop might evaporate, or perhaps be taken up by a blade of grass or other plant. The rain drop might fall on the ground and form a puddle or run off across hard packed soil or pavement. This water will likely evaporate, infiltrate the soil or travel to a stream and ultimately flow to an ocean; at any point along this journey water can evaporate and start again. The average time for water to go from rain to stream flow to oceans ranges between 16 and 26 days. Mankind has interrupted the flow of streams and rivers to the oceans by diverting water for irrigation and building reservoirs, thus slowing or interrupting its flow to the ocean. http://pubs.usgs.gov/circ/2007/1308/pdf/C1308_508.pdf

Not all surface water flows to oceans. Some lakes and wetlands have no surface drainage. They lose water to evaporation and to groundwater. Water moves much more slowly in the subsurface than in the atmosphere or on land surface. Water that infiltrates the soil can remain in the unsaturated zone where it is returned to the atmosphere by evaporation or plant transpiration or the water it can discharge to the surface in a channel becoming surface flow; or it can begin the longer journey- traverse the unsaturated zone and recharge an underlying aquifer. The water that remains in the unsaturated zone typically remains in the subsurface less than a year. Infiltrated water that travels to the saturated zone, and becomes recharge for the aquifer spends much more time in the subsurface. The time that it takes for water to travel through the entire thickness of the unsaturated zone varies tremendously. It can take mere hours to travel through thin unsaturated zones in humid regions to millennia, for thick unsaturated zones in arid regions. The types of soil and rock, the amount of overburden and ground cover and the thickness of the unsaturated zone determines the travel time.

The available supply of fresh water is limited to that naturally renewed by the hydrologic cycle or artificially replenished by the activities of mankind. The recharge rate, the amount of natural replenishment, varies with weather and can exceed water demands during unusually wet periods or fall far below demands during drought periods. Despite conservation the need for water continues to grow planet wide with the growth of human population and the development of emerging economies.