Climate change blamed as erratic downpours hit Pakistan’s harvests

Late rains were unusually heavy this year, say local farmers, affecting winter crops of wheat, oilseed and potato.

Anxious farmers in Pakistan waited for weeks for the rains to arrive – but when the skies finally opened, the downpour was so intense it destroyed crops and put the harvest in jeopardy.

"We weather scientists are really in shock, and so are farmers, who have suffered economic losses due to crop damage," says Muzammil Hussain, a weather forecasting scientist at the Pakistan Meteorological Department (PMD).

"The wind from the southeast has carried moisture from the Arabian Sea. Normally, the northeast wind brings rain during winter, and the southeast wind brings monsoon rains in summer. But the pattern has changed this year because of what is believed to be global warming."

Farmers across much of Pakistan plant winter crops of wheat, oilseed and potato late in the year and wait for rains to water the land.

This year, the rains arrived more than three weeks late and were unusually heavy, accompanied by violent hailstorms. Along with the rains, temperatures also dropped.

Ibrahim Mughal, chairman of the Pakistan Agri Forum, says excessive moisture due to heavy bouts of late rain is likely to lead to outbreaks of fungus on crops, and production could be halved.

"If the rains come a month ahead of the harvesting time [April to mid-May], it is always disastrous," he says. "It can hit production for a crop such as wheat by between 20% and 30%, and if the rain is accompanied by hailstorms and winds then the losses can escalate to more than 50%."

Arif Mahmood, a former director general at PMD, says the onset of winter across much of Pakistan is being delayed by two to three days every year, and there is an urgent need for farmers to adapt to such changes.

"Over recent years, winter has been delayed by 25 to 30 days, and also the intensity of the cold has increased, which has affected almost every field of life − from agriculture to urban life."

This year has also been marked by abrupt changes in temperature. Ghulam Rasul, a senior scientist at PMD, says big swings in temperature are likely to add to the problems being faced by millions of farmers in Pakistan.

"The average temperature during the first two weeks [of March] was between 11 and 13 degrees Celsius, but now it’s on a continuous upward trend and has reached 26˚C over the space of two days," he reports.

"The winter rains in the north and central area of Pakistan, and the sudden rise and fall in temperature, are related to climate change."

Serious damage

Similar storms and late winter rains have also caused serious damage across large areas of northern India.

The states of Uttar Pradesh and Maharashtra – the two most populous states in the country – have been particularly badly hit.

In Maharashtra, snow and landslides have blocked roads and cut off towns and villages.

In Uttar Pradesh, there are fears that more than 50% of the wheat crop has been lost in the eastern part of the state. More

This article was produced by the Climate News Network

For the Pakistan Metorlogical Department to claim be shocked by this event says to me that they have obviously not been following the global climate change discussion. Farming methods and water control and harvesting will have to change to mitigate the changing climate. Permaculture farming methods would be a good place to start. See http://permaculturenews.org/about-permaculture-and-the-pri/ Editor

 

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Explaining Extreme Events of 2013

A report released today investigates the causes of a wide variety of extreme weather and climate events from around the world in 2013. Published by the Bulletin of the American Meteorological Society, "Explaining Extreme Events of 2013 from a Climate Perspective (link is external)" addresses the causes of 16 individual extreme events that occurred on four continents in 2013. NOAA scientists served as three of the four lead editors on the report.

Of the five heat waves studied in the report, human-caused climate change was found to have clearly increased the severity and likelihood of those events. On the other hand, for other events examined like droughts, heavy rain events, and storms, fingerprinting the influence of human activity was more challenging. Human influence on these kinds of events—primarily through the burning of fossil fuels—was sometimes evident, but often less clear, suggesting natural factors played a far more dominant role.

"This annual report contributes to a growing field of science which helps communities, businesses and nations alike understand the impacts of natural and human-caused climate change," said Thomas R. Karl, L.H.D., director of NOAA’s National Climatic Data Center. "The science remains challenging, but the environmental intelligence it yields to decision makers is invaluable and the demand is ever-growing."

Confidence in the role of climate change about any one event is increased when multiple groups using independent methods come to similar conclusions. For example, in this report, five independent research teams looked at specific factors related to the record heat in Australia in 2013. Each consistently found that human-caused climate change increased the likelihood and severity of that event. However, for the California drought, which was investigated by three teams from the United States, human factors were found not to have influenced the lack of rainfall. One team found evidence that atmospheric pressure patterns increased due to human causes, but the influence on the California drought remains uncertain.

When human influence for an event cannot be conclusively identified with the scientific tools available today, this means that if there is a human contribution, it cannot be distinguished from natural climate variability.

"There is great scientific value in having multiple studies analyze the same extreme event to determine the underlying factors that may have influenced it," said Stephanie C. Herring, PhD, lead editor for the report at NOAA’s National Climatic Data Center. "Results from this report not only add to our body of knowledge about what drives extreme events, but what the odds are of these events happening again—and to what severity."

The report was edited by Herring, along with Martin P. Hoerling, NOAA’s Earth System Research Laboratory; Thomas Peterson, NOAA’s National Climatic Data Center, and Peter A. Stott, UK Met Office Hadley Centre and written by 92 scientists from 14 countries. View the full report online (link is external).

Also, view the slides for the media briefing on the "Explaining Extreme Events of 2013 from a Climate Perspective" report. More

 

© 2014

Third National Climate Assessment: Climate Change Impacts in the United States

Please see the message below announcing the release of the new U.S. National Climate Assessment and the associated websites where it is available.

We are so pleased to announce today’s release of the Third National Climate Assessment: Climate Change Impacts in the United States. The Third National Climate Assessment (NCA), which delivers on USGCRP’s legal mandate and the President’s Climate Action Plan, is the most comprehensive, authoritative, transparent scientific report ever generated on U.S. climate impacts, both as currently observed and as projected for the future. The Third NCA documents climate change-related impacts and responses across key sectors and all regions of the U.S. with the goal of better informing public and private decision-making at all levels.

WHERE CAN YOU FIND THE ASSESSMENT?

The Third NCA is available to download and also can be explored in a novel interactive format through USGCRP’s newly redeployed web presence at http://globalchange.gov. An important feature of this interactivity is the traceability of the data and other information in the report, giving users the means to refer back to these data for their analyses and decision support. The site is mobile-compatible and every piece of the report—from highlights to chapters to key messages to graphics—has its own unique URL for social network sharing. Please find below links that will help you navigate the Third NCA:

· Full Report: http://nca2014.globalchange.gov/

· Highlights: http://nca2014.globalchange.gov/highlights

Beyond the Third NCA, the new globalchange.gov features accessible and dynamic information on a wide range of climate-related topics.

Any White House materials about the release of the Third NCA will be available from: http://www.whitehouse.gov/climate-change. At 2:00 pm EDT, the White House is hosting a stakeholder event that will feature speakers from the Administration, NCA authors, and users of the report. For those who won't be at the event in person, you can tune into the live webcast:http://www.whitehouse.gov/live.

WHAT CAN BE FOUND IN THIS LATEST ASSESSMENT?

The data and information in the Third NCA can be of great value to the adaptation planning and implementation efforts of U.S. Federal Agencies and their partners and stakeholders. Some examples include:

· The latest science on observed trends and projected future conditions of changes in the climate across the 8 NCA regions and contiguous U.S. as well as 13 sectors and cross-sectors.

· Examples throughout of on-the-ground impacts across the U.S., many of which are already directly affecting substantial numbers of Americans.

· For the first time in a U.S. national assessment, explicit chapters on Decision Support, Mitigation, and Adaptation, with specific information on those topics as they are practiced now in addition to identifying research needs associated with these topics for improving future implementation of climate resilience measures. Specifically related to adaptation, the following information is captured in the Adaptation chapter:

o Adaptation key terms defined

o An overview of adaptation activities at multiple levels including the Federal government, states, tribes, local and regional governments, non-governmental organizations, and the private sector

o Example barriers to adaptation

o Several illustrative case studies of adaptation in action

· A useful and informative section that answers some frequently asked questions about climate change. The questions addressed range from those purely related to the science of climate change to those that extend to some of the issues being faced in consideration of mitigation and adaptation measures.

· Data and metadata behind content and images used in the assessment are accessible and traceable.

 

 

© 2014

India’s rain woes grow bigger, scientists worried

Forecasting the June-to-September rains, which account for three-quarters of India’s annual rainfall, is becoming tougher. Last year, six states had to declare droughts despite predictions of a normal monsoon.

Although India is scaling up its prediction techniques, including joint Indo-American forecasting under a bilateral agreement, too little is understood about how pollution and rising temperatures are impacting the monsoon. But new research shows that they are surely having an impact on the climate.

“Our studies show the Indian Ocean has significantly warmed in 50 years. By about 0.6 degrees. Monsoon has been declining in the Western Ghats, and interior areas, such as Jharkhand and Chhattisgarh, by about 6-7%,” R Krishnan, a climatologist at the Indian Institute of Tropical Meteorology, Pune, told HT.

Krishnan also said that a weakening monsoon circulation has quickened the “warming of the equatorial India Ocean” and this, in turn, has contributed to a “further weakening of the monsoon”.

The new findings portend problems India isn’t currently prepared to address. Two-thirds of Indians rely on rain-fed farm income. The monsoon also replenishes 81 nationally monitored water reservoirs critical for drinking, power and irrigation. A changing monsoon could hurt millions of farmers.

Yet another published study, by Dr Veerabhadran Ramanathan of the University of California, San Diego, notes that climate change has “evidently already negatively affected India’s hundreds of millions of rice producers and consumers. More

 

© 2014

IPCC AR5 Working Group II Video Overview

AR5 Working Group II

 

Published on Mar 30, 2014 • IPCC Fifth Assessment Report - Working Group II - Climate Change 2014: Impacts,

Adaptation, and Vulnerability

© 2014

Northeast Pakistan hit by 'surprise' floods, as monsoon rains intensify

SIALKOT, Pakistan (Thomson Reuters Foundation) - “We kept quivering with fear the whole night and could not sleep even a wink,” recalled Salma Zehra, a mother of five teenage children. The family trembled to think that the roof of their mud house could cave in at any time, as the rain lashed down in a huge thunderstorm.

Mehtabpur, District Sialkot, Pakistan

By early morning on July 22, the house in Mehtabpur village in northeast Pakistan’s Sialkot district was waist-deep in water. The torrential downpour had left Zehra’s two buffaloes dead, the 45-year-old said in a shaky voice.

Another bout of heavy rain followed later that night. The Dek tributary of the Chenab River in Sialkot, 192 km (122 miles) from Islamabad, burst its banks, submerging more than 72 villages in the district.

Besides Sialkot, other districts in Punjab province have also suffered massive damage to crops across 1,000 hectares of land, as well as to properties. According to the district disaster management authorities of Sialkot, Gujranwala and Narowal, an estimated 400 villages have been flooded.

Officials have declined to give final figures for the losses, but say dozens have died and thousands of people remain stranded in the affected parts of the three districts. Some are starting to return home, but many houses have collapsed and must be rebuilt, they report.

Sialkot District Coordination Officer Iftikhar Ali Sahu told Thomson Reuters Foundation thousands of people had been trapped on the roofs of their houses during the worst of the flooding. “Mortality among cattle is high - the number of dead animals continued to rise as the floodwaters began to recede on July 26,” he added.

The situation in adjoining districts is just as bad. In Narowal alone, around 2,000 people were marooned on their rooftops in some seven villages a week ago.

Less than 30 percent of the floodwater has yet to recede, according to Mujahid Sherdil, director-general of the Punjab Provincial Disaster Management Authority.

Machines have been brought in to help drain water out of the flood-affected areas, and he hopes the task will be accomplished in the next two to three days, he told Thomson Reuters Foundation from Lahore.

Sherdil said the torrential rainfall had caused breaches of irrigation canals, streams and natural dams, and the floods had washed away crops, livestock, roads, bridges, buildings and even entire villages.

Farmers say surviving cattle in flood-hit areas are now at risk.

“Besides paddy, maize and vegetable crops, fodder fields are also underwater. This has created an acute shortage of fodder, and it is barely possible to save our cattle from the looming threat of hunger and disease,” said Zehra’s husband, Ghulam Abbas.

METEOROLOGISTS ‘STARTLED’

The above-normal monsoon rains in Punjab’s northeastern districts have taken weather experts by surprise.

“Last month, we predicted that this year monsoon rains across the country would remain normal with no possibility of flooding. But unexpected heavy rains in the northeastern districts are startling for us,” said Ghulam Rasul, a senior weather scientist at the Pakistan Meteorological Department (PMD) in Islamabad. “This shows how monsoon rains have become erratic and unpredictable in timing, volume and intensity.”

Sherdil, head of the Punjab disaster management agency, said the heavy rains and flooding had caught them unprepared.

“We were closely following the weekly and monthly forecasts of PMD that never predicted heavy rains of unprecedented significance for July in northeastern parts, which have been nearly 40 percent above normal for the month,” he said.

It has been difficult to get aid into the affected areas due to damaged and flooded roads and bridges, he said. “Nevertheless, we left no stone unturned to get the emergency relief items including food, medicines, to the flood victims on boats – although (they arrived) a bit late,” he added.

MONSOON SHIFTS

In June 2012, scientists argued in the Nature Climate Change journal that global warming would make understanding changes in the South Asian monsoon more difficult.

They said the impacts of short- and long-term monsoon shifts would affect the lives of over a billion people in the region, who rely on rainfall for agriculture, hydropower generation, economic growth and basic human needs.

Understanding how the South Asian monsoon will alter due to climate change is necessary to cope with the effects, reduce the risk of disasters and safeguard people’s livelihoods, they underlined.

“Addressing the uncertainties in projected changes of the monsoon variability in coming years will remain a daunting challenge for climate scientists,” said Arshad Abbasi, a water and energy expert at the Sustainable Development Policy Institute in Islamabad.

Arshad Khan, the executive director of the Global Change Impact Study Centre (GCISC), the research arm of Pakistan’s Federal Climate Change Division, said the country is in the grip of unpredictable weather patterns.

Intense monsoon rains will be a common phenomenon, particularly on the country’s southern plains which lack water reservoirs and are highly vulnerable to floods, he warned.

And a spurt in the speed of glacial melt, due to rising global temperatures and above-normal monsoon rains, is likely to cause rivers to overflow and burst their banks across the country, he added.

GOVERNMENT EFFORTS

Officials at the Climate Change Division, which operates under the oversight of the prime minister, said efforts are underway to tackle the vagaries of climate change across different sectors of the economy, particularly agriculture and water.

“Consultations are being made with national and provincial disaster management authorities, and officials of federal and provincial environment, agriculture, irrigation departments to implement national climate change policy to mitigate the impacts of changing weather patterns and erratic monsoon rains,” said a senior official, who coordinates policy at federal and provincial levels.

The Climate Change Division is developing climate adaptation plans for the agriculture, water and irrigation sectors, which will be implemented in Pakistan’s four provinces in collaboration with international NGOs and provincial government offices.

It is also working on programmes to ensure that climate change is considered in other sectors such as health and education, to make them more climate-resilient.

Abbasi of the Sustainable Development Policy Institute said the best ways to avert the growing threat of floods in Pakistan include efficient watershed management, reforestation in northern mountain areas and the revival of riverine forests.

Saleem Shaikh and Sughra Tunio are Islamabad-based journalists specialising in climate change and development issues. More

Rivers' in air could boost flooding

Winter floods could intensify in Britain, [and countries globally] according to new research into powerful weather systems called "atmospheric rivers".

Only identified about 20 years ago, atmospheric rivers are intense bands of moisture that flow through the air.

Known to be responsible for heavy rainfall, they have been blamed for severe flooding in California and the UK.

The new study suggests that warmer conditions could create more rivers - and make them more severe.

The paper is published by the Institute of Physics in Environmental Research Letters.

Atmospheric rivers are up to 300km wide and can stretch in length for over 1,000-2,000km. They flow invisibly between 1-2.5km above the surface of the ocean.

One atmospheric river is believed to have been behind the violent flooding that hit Cockermouth in Cumbria on 19 November 2009.

The flooding claimed the life of a policeman, PC Bill Barker, who died after a bridge collapsed.

The researchers, led by Dr David Lavers of the University of Iowa, have estimated the staggering volume of moisture carried by this particular atmospheric river.

They calculate that at its peak it was transporting almost 300,000 tonnes of moisture every second.

By comparison, the River Thames carries about 65 tonnes of water through London over the same period.

Remain on course

If the rivers make landfall and encounter a steep rise in terrain, the air is forced upwards where it cools and releases the moisture in the form of rain.

On top of that, if the river remains on the same course for 24 hours - as it did over Cumbria in 2009 - it will deliver a continuous flow of heavy rain over the same area.

The most closely-studied atmospheric river, which flows towards the California coast, has been dubbed the "Pineapple Express" because it usually originates from the region of Hawaii.

It has been linked to a number of extremely damaging storms along the US West Coast.

Over the last 30 years, there has been an average of 9-11 of the strongest atmospheric river events hitting Britain every year.

In this latest study, the researchers examined five different modelling scenarios to simulate possible conditions this century and found that a warming climate - which allows the atmosphere to hold more moisture - made the rivers more likely.

Dr Lavers said: "All five models suggest that there could be a doubling of atmospheric river events in the period 2074-99 and most of those could be expected to make landfall in the UK.

"One of the big things is that these are the most relevant feature of winter flooding in Britain and the work is certainly suggesting an increase in strength and frequency."

Computer modelling

Among the uncertainties about the research are the reliability of the models used to generate the future scenarios and possible shifts in the patterns of the winds - a change of course away from the UK would reduce the risk.

It was research in the 1970s that first identified "conveyor belts" of moisture travelling through the atmosphere, with later studies in the early 1990s detecting much narrower bands of intense vapour that became known as atmospheric rivers.

Dr Richard Allan of Reading University, also an author of the paper, said: "What this shows is that the dominating factor is the increase in water vapour which means that if you've got more moisture - and the winds don't change -then you've got a much bigger potential for flooding.

"These are really massive flows of invisible water which can feed clouds and cause rainfall if forced up over mountains."

The researchers say the study could help guide forecasters trying to give warning of future flood risks. More

 

Killer Heat Waves and Floods Linked to Climate Change

UXBRIDGE, Canada, Feb 27 2013 (IPS) - Killer heat waves, floods and storms are increasingly caused by climate change, new research reveals.

Scientists in Germany say they have found how greenhouse gases from burning fossil fuels are helping to trap the jet stream, resulting in extraordinary weather such as the 2010 Pakistan flood and the 2011 heat wave in the United States.

Human-driven climate change repeatedly disturbs the flow of atmospheric waves around the globe’s Northern hemisphere, said lead author Vladimir Petoukhov of the Potsdam Institute for Climate Impact Research (PIK) in Germany.

Giant atmospheric waves called Rossby waves are meanders in the strong, high-altitude winds known as jet streams and have a major influence on weather. These wave movements are caused by the difference in temperatures between the cold air from the Arctic and hot air from the tropics.

When the waves shift north, they suck warm air from the tropics to Europe, Russia, or the U.S., and when they swing down, they do the same thing with cold air from the Arctic, said Petoukhov.

“During several recent extreme weather events, these planetary waves almost freeze in their tracks for weeks,” he said. “So instead of bringing in cool air after having brought warm air in before, the heat just stays.”

This unnatural pattern is due to human heating of the climate through emissions of greenhouse gases that result from burning fossil fuels, according to the study published this week in Proceedings of the National Academy of Sciences.

However, this heating of the atmosphere is wildly uneven. The Arctic is warming two to three times faster than the global temperature rise of 0.8C and that affects the Rossby waves and is slowing the jet stream.

“(Our research) complements previous research that already linked such phenomena to climate change,” said Hans Joachim Schellnhuber, a co-author of the study.

IPS previously reported research showing the dramatic loss of Arctic sea ice and rapid warming of the region was affecting weather patterns in the northern hemisphere.

The unprecedented expanse of ice-free Arctic Ocean has been absorbing the 24-hour sun over the short polar summer. The heat in the water must be released into the atmosphere if the ice is to re-form in the autumn.

“This is like a new energy source for the atmosphere,” Jennifer Francis, a researcher at Rutgers University, told the Guardian.

Major declines of Arctic summer sea ice as in 2011 and 2007 have been linked to colder winters in the UK and northern Europe, Francis said. The record ice loss in 2012 has been followed by a cold and stormy winter over much of Europe.

“The jet stream is clearly weaker,” said Francis. That means weather systems, be it rain or dry conditions, are slow to move on and last longer. Ultimately, this can result in “blocking” events, such as the conditions that produced the terrible heatwave in western Russia during the summer of 2010 and floods in Pakistan, she said.

Last summer, Greenland experienced a similar blocking anti-cyclone, resulting in a record surface melting of its ice sheet. “Blocks act like a traffic jam, slowing down weather patterns elsewhere,” Francis said.

Scientists are surprised by how extreme these changes have been with a relatively small amount of warming. That has prompted some to speak out politically to urge emission reductions. On Monday, a group of Canadian and U.S. scientists pleaded with the Canadian government to stop the expansion of the Alberta tar sands oil projects and take real steps to reduce carbon emissions. More

 

 

Extreme Weather

The weekend forecast for Nashville, Tennessee, called for two to four inches of rain. But by the afternoon of Saturday, May 1, 2010, parts of the city had seen more than six inches, and the rain was still coming down in sheets.

Mayor Karl Dean was in the city’s Emergency Communications Center monitoring the first reports of flash flooding when something on a TV screen caught his eye. It was a live shot of cars and trucks on Interstate 24 being swamped by a tributary of the Cumberland River southeast of the city. Floating past them in the slow lane was a 40-foot-long portable building from the Lighthouse Christian School.

“We’ve got a building running into cars,” the TV anchorman was saying.

Dean had been in the “war room” for hours. But when he saw the building floating down the highway, he says, “it became very clear to me what an extreme situation we had on our hands.” Soon 911 calls were coming in from every part of the city. Police, fire, and rescue teams were dispatched in boats. One crew in a skiff headed out to I-24 to pluck the driver of an 18-wheeler from the chest-high water. Other teams pulled families off rooftops and workers from flooded warehouses. Still, 11 people died in the city that weekend.

This was a new kind of storm for Nashville. “It came down harder than I’ve ever seen it rain here,” says Brad Paisley, the country singer, who owns a farm outside town. “You know how when you’re in a mall and it’s coming down in sheets, and you think, I’ll give it five minutes, and when it lets up I’ll run to my car? Well, imagine that it didn’t let up until the next day.”

Over at NewsChannel 5, the local CBS station, meteorologist Charlie Neese could see where the weather was coming from. The jet stream had gotten stuck over the city, and one thunderstorm after another was sucking up warm, humid air from the Gulf of Mexico, rumbling hundreds of miles northeast, and dumping the water on Nashville. While Neese and his colleagues were broadcasting from a second-floor studio, the first-floor newsroom was being swamped by backed-up sewers. “Water was shooting up through the toilets,” Neese says.

The Cumberland River, which winds through the heart of Nashville, started rising Saturday morning. At Ingram Barge Company, David Edgin, a former towboat captain, had more than seven boats and 70 barges out on the waterway. As the rain continued to pound down, he called the U.S. Army Corps of Engineers to get its forecast of how high the river would rise. “It’s blowing up our models,” the duty officer said. “We’ve never seen anything like this.” Edgin ordered all of Ingram’s boats to tie up at safe locations along the riverbank. It turned out to be a smart move.

By Saturday night the Cumberland had risen at least 15 feet, to 35 feet, and the corps was predicting it would crest at 42. But the rain didn’t stop Sunday, and the river didn’t crest until Monday—at 52 feet, 12 feet above flood stage. Spilling into downtown streets, the flood caused some two billion dollars in damage. More

When one starts to look at the bigger picture of extreme weather around the world you quickly realize that something is ot right. Climate change anyone? Editor

 

The Battle for Water - Harvesting and conserving rainwater key to boosting crop yields

In its Rio+20 call for action, CGIAR urged Rio+20 actors to address the unequal sharing and unsustainable use of natural resources such as water and land, through improved governance and technology dissemination. World food production, hence food security depends on water but water availability per capita is drastically decreasing.

To sustainably ensure a steady food production especially in poor smallholdings in the (global) south, mainly practicing rain fed agriculture, one priority is to help local rural communities better manage “green water” – the rainwater captured by the soil and available for plants.

For decades the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) has been working on successful local and farmer participatory water governance models.

Whether it's bread, meat, milk or bananas, whatever we eat demands water. But with a rapidly growing population (already more than 7 billion people), water availability gets more and more scarce.

There is a correlation between poverty, hunger and water stress. The UN Millennium Project has identified the "hot spot" countries in the world with the highest number of malnourished people.

These countries coincide closely with semi-arid and dry sub-humid hydroclimates, savannahs and steppe ecosystems, where rainfed agriculture is the dominating source of food, and where water constitutes a key limiting factor to crop growth.

The Food and Agriculture Organisation (FAO) estimates that we need to increase agricultural production by 70% to feed the projected 9 billion people expected on the planet by 2050. But, given the current global food crisis, boosting agricultural production will certainly increase water stress.

PRODUCING MORE WITH LESS WATER

We urgently need to increase water productivity. But how do we produce more cereals, milk and bananas with less water? And what type of water are we talking about?

At the last World Water Forum in Marseille in March, experts talked about the colour of water: blue water (irrigation), green water (rainwater captured by the soil and available for plants) and grey water (polluted water that could be treated and recycled). More

The world is closer to a food crisis than most people realise

Unless we move quickly to adopt new population, energy, and water policies, the goal of eradicating hunger will remain just that.

Food riots in Algeria in 2008. Photograph: Fayez Nureldine/AFP/Getty Images

In the early spring this year, US farmers were on their way to planting some 96m acres in corn, the most in 75 years. A warm early spring got the crop off to a great start. Analysts were predicting the largest corn harvest on record.

The United States is the leading producer and exporter of corn, the world's feedgrain. At home, corn accounts for four-fifths of the US grain harvest. Internationally, the US corn crop exceeds China's rice and wheat harvests combined. Among the big three grains – corn, wheat, and rice – corn is now the leader, with production well above that of wheat and nearly double that of rice.

The corn plant is as sensitive as it is productive. Thirsty and fast-growing, it is vulnerable to both extreme heat and drought. At elevated temperatures, the corn plant, which is normally so productive, goes into thermal shock.

Time is running out. The world may be much closer to an unmanageable food shortage – replete with soaring food prices, spreading food unrest, and ultimately political instability– than most people realise.

As spring turned into summer, the thermometer began to rise across the corn belt. In St Louis, Missouri, in the southern corn belt, the temperature in late June and early July climbed to 100F or higher 10 days in a row. For the past several weeks, the corn belt has been blanketed with dehydrating heat.

Weekly drought maps published by the University of Nebraska show the drought-stricken area spreading across more and more of the country until, by mid-July, it engulfed virtually the entire corn belt. Soil moisture readings in the corn belt are now among the lowest ever recorded.

While temperature, rainfall, and drought serve as indirect indicators of crop growing conditions, each week the US Department of Agriculture releases a report on the actual state of the corn crop. This year the early reports were promising. On 21 May, 77% of the US corn crop was rated as good to excellent. The following week the share of the crop in this category dropped to 72%. Over the next eight weeks, it dropped to 26%, one of the lowest ratings on record. The other 74% is rated very poor to fair. And the crop is still deteriorating.

Over a span of weeks, we have seen how the more extreme weather events that come with climate change can affect food security. Since the beginning of June, corn prices have increased by nearly one half, reaching an all-time high on 19 July. More