Tuesday, June 30, 2015

Groundwater from aquifers important factor in food security

Thirsty cities, fields and livestock drink deeply from aquifers, natural sources of groundwater. But a study of three of the most-tapped aquifers in the United States shows that overdrawing from these resources could lead to difficult choices affecting not only domestic food security but also international markets.

University of Illinois professors of civil and environmental engineering Ximing Cai and Megan Konar, along with graduate student Landon Marston and Lehigh University professor Tara Troy, studied groundwater consumption from three main systems. Reliance on these aquifers intensified so much from 2000 to 2008 that it accounted for 93 percent of groundwater depletion in the U.S. They published their findings in the Proceedings of the National Academy of Sciences.

The U.S. Geological Survey identifies the Central Valley aquifer in California, the High Plains aquifer in the Great Plains states, and the Mississippi Embayment aquifer in the lower Midwest as being managed unsustainably, which means that is being extracted from the aquifer faster than it is replenishing.

"Deep groundwater is like natural gas. If you use it, it takes a while to recharge," Cai said. "Unsustainable usage means the water table is lowered, which makes it more difficult and more expensive to pump water since we have to keep going deeper. It also affects ecosystems associated with the water table, such as streams and wetlands."

The researchers tracked water consumption from the aquifers to see where the water was going, both in terms of geography and usage. For example, when water was used to irrigate a crop, the researchers tracked where those crops were shipped.

"When we think of water, we think of direct water, the water that comes out of our faucets. But we actually use a lot of embodied water in our everyday lives – the water footprint to produce a product," Konar said. "We looked at the water implicitly being transferred between states and countries in the products."

The researchers found that the vast majority – 91 percent – of embodied groundwater from these three aquifers stayed within the U.S. The remaining 9 percent was exported internationally. They identified the states most heavily reliant on each aquifer, and the breakdown of what was produced using water from each aquifer. For example, the largest percentage of water from the High Plains aquifer irrigated grains, while the largest contribution from the Central Valley aquifer in California went to producing meat. See the infographic for the detailed findings.

The researchers hope that having detailed information on how aquifer water is used, and the complex economic and environmental implications of that use, can help policy makers in their decisions about water resource management.

"The issue here is the tradeoffs. That's the difficulty for the decision makers," Cai said. "There is a tradeoff between the environment and economic profit, and there is a trade-off between the current use and future use. The environment is affected, the food markets are affected, the resources for fisheries are affected. That helps the decision makers understand the issue. I think this information is also important for the public to understand the issue."

The researchers feel that the study is also important for international leaders, as any decisions will affect global food production and prices. Although the international exports represented a small percent of the overall water consumption, the exported goods account for a large market share in the countries that import them, the study found.

Next, the researchers plan to study major watersheds in the U.S. to gain a more comprehensive picture of natural water resources in the United States. They are interested in detailing water use under variable conditions, both in terms of economic and environmental impact.

"Managing water resources for the future is especially important because future rainfall patterns are going to be more variable, with more droughts predicted," Konar said. "As we're seeing in California, they were really lucky to have aquifers to rely on during a drought. We don't want to deplete these aquifer supplies, so that when we get into these drought situations, we have some emergency backup." More

More information: "Virtual groundwater transfers from overexploited aquifers in the United States" PNAS 2015 ; published ahead of print June 29, 2015, DOI: 10.1073/pnas.1500457112


Wednesday, June 24, 2015

Century of Water Shortage Ahead? Lake Mead Drops Below Rationing Line For First Time in Its History.

Lake Mead Drops Below Rationing Line For First Time in Its History.

1075 feet. That’s the water level Lake Mead must stay above before mandatory multi-state water rationing goes into effect. A level just 25 feet above the highest intake pipe used to supply cities across the Desert Southwest. Last night water levels at the key national water storage facility fell below that hard line to 1074.99 feet — a record low never before seen in all of its history.

If water levels remain below the 1075 foot mark through January of 2016, then a multi-state rationing will go into effect (with most acute impacts for Arizona and Nevada). A rationing that will have serious consequences for desert cities across the Southwest, cities like Las Vegas which rely on Lake Mead for so much of their water.

Despite Lake Mead hitting the 1075 hard line, it appears that rationing may be forestalled through 2016. It’s a silver lining of all the severe summer storms that have rolled through the Colorado River Basin this spring and summer — pumping up water flows to Lake Mead and Lake Powell. A flush of much needed moisture that will, hopefully, prevent water rationing from going into effect during 2016. But prospects for the future, despite this temporary respite, are starting to look a bit grim.

Risk of Future Megadrought

The trend set in place by a human-forced warming of the Desert Southwest has resulted in an increasing number of dry years. The added heat forces water to evaporate more rapidly. So even when it does rain an average amount, moisture levels still fall. The result is not only an increase in single year droughts, but an increased risk of decadal droughts (called megadroughts).

As the years progress and more of the impacts of human-forced global warming become apparent, the drought impacts and severe drought risks are only expected to rise. For according to a recent Cornell University report (2014) the chance of a 10 year drought for the US Southwest under a moderate warming scenario (RCP 4.5) is 50% this century (greater for states like Texas, Oklahoma, New Mexico, Arizona, and Nevada — see graphic below). The chances of a 30 year drought range from 20-50 percent depending on the severity of the human greenhouse gas emission. More


Parched Caribbean faces widespread drought, water shortages

The worst drought in five years is creeping across the Caribbean, prompting officials around the region to brace for a bone dry summer.

From Puerto Rico to Cuba to the eastern Caribbean island of St. Lucia, crops are withering, reservoirs are drying up and cattle are dying while forecasters worry that the situation could only grow worse in the coming months.

Thanks to El Nino, a warming of the tropical Pacific that affects global weather, and a quieter-than-normal hurricane season that began in June, forecasters expect a shorter wet season. That means less rain to help refill Puerto Rico's thirsty Carraizo and La Plata reservoirs as well as the La Plata river in the central island community of Naranjito. A tropical disturbance that hit the U.S. territory on Monday did not fill up those reservoirs as officials had anticipated.

Puerto Rico is among the Caribbean islands worst-hit by the , with more than 1.5 million people affected by the drought so far, according to the U.S. National Drought Mitigation Center.

Tens of thousands of people receive water only every third day under strict rationing recently imposed by the island government. Puerto Rico last week also activated National Guard troops to help distribute water and approved a resolution to impose fines on people and businesses for improper water use.

The Caribbean's last severe drought was in 2010. The current one could grow worse if the hurricane season ending in November produces scant rainfall and the region enters the dry season with parched reservoirs, said Cedric Van Meerbeeck, a climatologist with the Caribbean Institute for Meteorology and Hydrology.

"We might have serious water shortages ... for irrigation of crops, firefighting, domestic consumption or consumption by the hotel sector," he said.

The Caribbean isn't the only area in the Western Hemisphere dealing with extreme water shortages. Brazil has been struggling with its own severe drought that has drained reservoirs serving the metropolis of Sao Paulo.

In the Caribbean, the farm sector has lost more than $1 million in crops as well as tens of thousands of dollars in livestock, said Norman Gibson, scientific officer at the Trinidad-based Caribbean Agricultural Research and Development Institute.

On St. Lucia, which has been especially hard hit, farmers say crops including coconuts, cashews and oranges are withering.

"The outlook is very, very bad," said Anthony Herman, who oversees a local farm cooperative. "The trees are dying, the plants are dying ... It's stripping the very life of rivers."

Officials in Cuba say 75 percent of the island is enduring a drought that has killed cattle and destroyed thousands of hectares (acres) of crops including plantains, citrus, rice and beans. Recent heavy rains in some areas have alleviated the problem some, but all 200 government-run reservoirs are far below capacity.

In the nearby Dominican Republic, water shortages have been reported in hundreds of communities, said Martin Melendez, a civil engineer and hydrology expert who has worked as a government consultant. "We were 30 days away from the entire water system collapsing," he said.

The tourism sector has also been affected.

Most large hotels in Puerto Rico have big water tanks and some recycle wastewater to irrigate green areas, but many have curtailed water use, said Frank Comito, CEO of the Florida-based Caribbean Hotel & Tourism Association.

Other hotels have cut back on sprinkler time by up to 50 percent, said Carlos Martinez of Puerto Rico's Association of Hotels. "Everybody here is worried," he said. "They are selling water tanks like hot cakes ... and begging God for rain."

Guests at Puerto Rico's El Canario by the Lagoon hotel get a note with their room keys asking them to keep their showers short amid the water shortage. "We need your cooperation to avoid waste," says the message distributed at the front desk of the hotel in the popular Condado district.

At the Casa del Vega guesthouse in St. Lucia, tourists sometimes find the in their rooms turned off for the day, preventing them from taking a shower. "Even though we have a drought guests are not sympathetic to that," hotel manager Merlyn Compton said. More


Monday, June 22, 2015

Society will collapse by 2040 due to catastrophic food shortages, says Foreign Office-funded study

A scientific model supported by the [UK's] Foreign Office has suggested that society will collapse in less than three decades due to catastrophic food shortages if policies do not change.

The model, developed by a team at Anglia Ruskin University’s Global Sustainability Institute, does not account for society reacting to escalating crises by changing global behaviour and policies.

However the model does show that our current way of life appears to be unsustainable and could have dramatic worldwide consequences.

Dr Aled Jones, the Director of the Global Sustainability Institute, told Insurge Intelligence: "We ran the model forward to the year 2040, along a business-as-usual trajectory based on ‘do-nothing’ trends — that is, without any feedback loops that would change the underlying trend.

"The results show that based on plausible climate trends, and a total failure to change course, the global food supply system would face catastrophic losses, and an unprecedented epidemic of food riots.

"In this scenario, global society essentially collapses as food production falls permanently short of consumption."

The model follows a report from Lloyds of London which has evaluated the extent of the impact of a shock scenario on crop production, and has concluded that the "global food system is under chronic pressure."

The report said: "The global food system is under chronic pressure to meet an ever-rising demand, and its vulnerability to acute disruptions is compounded by factors such as climate change, water stress, ongoing globalisation and heightening political instability. More


Wednesday, June 17, 2015

To fight desertification, let's manage our land better

Every year, we lose 24 billion tons of fertile soil to erosion and 12 million hectares of land to desertification and drought. This threatens the lives and livelihoods of 1.5 billion people now.

In the future, desertification could displace up to 135 million people by 2045. Land degradation could also reduce global food production by up to 12% and push world food prices up by 30%. In Egypt, Ghana, Central African Republic, Pakistan, Tajikistan and Paraguay, land degradation could cause an annual GDP loss of up to 7%.

Pressure on land resources is expected to increase as populations grow, socio-economic development happens and the climate changes. A growing population will demand more food, which means that unsuitable or especially biodiverse land will be claimed for farming and be more vulnerable to degradation. Increased fertilizer and pesticide use related to agriculture will increase nutrient loading in soils, causing eutrophication and declines in fertility over time. Climate change will also aggravate land degradation—especially in drylands, which occupy 40% of global land area, and are inhabited by some 2 billion people. Urban areas, which are located in the world’s highly fertile areas, could grow to account for more than 5% of global land by mid-century.

Unless we manage our land better, every person will rely on just .11 hectares of land for their food; down from .45 hectares in 1960.

So how do we manage land better?

It will all come down to what we do with our soil, which is the most significant natural capital for ensuring food, water, and energy security while adapting and building resilience to climate change and shocks. The soil’s nutrient cycling provides the largest contribution (51%) of the total value (USD33 trillion) of all ‘ecosystem services’ provided each year. But soil’s important function is often forgotten as the missing link in our pursuit of sustainable development.

We must invest in applicable solutions that are transformative, and can be scaled up. Climate-smart agriculture is an alternative approach to managing land sustainably whilst increasing agricultural productivity. It includes land management options that sequester carbon and enhance resilience to climate change. Proven climate-smart practices such as agroforestry, integrated soil fertility management, conservation agriculture, and improved irrigation can ensure that land is used optimally, restored and managed in a manner that maximizes ecological, economic and social benefits.

But climate-smart agriculture requires conducive policy frameworks, increased investment, and judicious policy management. Rural poverty is often a product of policies that discriminate against small landholders, forcing them off the land, creating sub-optimal land use outcomes, and long term degradation. Secure land rights are necessary for climate-smart agriculture, providing incentives for local communities to manage land more sustainably. In Rwanda, for instance, land tenure reform rapidly doubled investment in soil conservation, with even larger increases for plots managed by female farmers.

Second, there is need for increased national investment in climate smart agriculture. For technologies such as conservation agriculture that require substantial up-front investment in machinery and other inputs, schemes such as those involving payment for ecosystem services may be more effective in promoting CSA technology adoption. For technologies such as agroforestry systems, innovative finance mechanisms that help farmers bridge the period between when trees are planted, mature and generate income can be decisive.

Third, in some cases, direct public investment in landscape restoration and rehabilitation can bring about sizeable livelihood benefits and create better conditions for attracting further investments by farmers and communities. The China Loess Plateau is a well-documented success story of landscape restoration. Similar experiences are happening in Ethiopia, Kazakhstan and Senegal.

Fourth, a number of improved land management technologies are knowledge-intensive, and promoting their adoption will require training. Conservation agriculture for instance entails sophisticated combinations of no-tillage, residue management, use of cover crops, and other activities and practices that many farmers have limited experience with. The knowledge base of local land management practices can also be improved through targeted capacity development programs.

Many demand-side interventions can strategically break the adoption barriers associated with climate-smart practices. These include: providing farmers with improved weather forecasting, weather-indexed crop insurance, and measures to reduce production variability such as drought-tolerant crops, deep-rooted crops, and irrigation. These should be combined with supply-side measures such as lowering trade barriers to increase national and regional market size, improving road and rail infrastructure to lower transport costs, and improving market information systems to increase farmers’ access to markets.

Lastly, public support is as crucial as the amount of support to fully realize the productivity, adaptation, and mitigation benefits in agriculture. Public support that focuses on research, investments in improved land management, and land tenure rather than on input support is generally more effective, benefits more farmers, and is more sustainable in the long run.

Actions to reduce the negative impacts of land degradation and desertification must indeed go hand in hand with interventions that eradicate poverty and address inequality. Without them, we will not end poverty and boost shared prosperity. More