Global warming disastrous to agriculture, too!

By Armando A. Mortejo
“I’m more worried about global warming than I am of any major military conflict,” United Nations weapons inspector Hanx Blix once said.
While the recent surge of super typhoons, severe droughts, continuous flooding, and other natural calamities have caught the attention of scientists from all over the world, no one seems to bother about the effects of global warming to agriculture.
Just how disastrous is global warming to agriculture can be summed up in this story written Danielle Nierenberg and Brian Halweil, which appeared in the “State of the World 2005” report:
“High in the Peruvian Andes, five hours by car from Cuzco and six hours by horseback, a new disease has invaded the potato fields in the town of Chacllabamba.  Warmer and wetter weather associated with climate change has allowed late blight — the same fungus that caused the Irish potato famine — to creep 4,000 meters up the mountainside for the first time since humans started planting tubers in this region thousands of years ago.
“In 2003, farmers here saw their crops almost totally destroyed.  Breeders are rushing to develop potatoes that retain the taste, texture, and quality preferred by local people and that also resist the ‘new’ disease.”
What happened in Peru is just a harbinger of the worst things to come.  “As farming depends so heavily on a stable climate, this industry will struggle more than others to cope with more erratic weather, severe storms, and change in growing season lengths,” the two authors surmised.
It is not happening in the Philippines yet but it may happen soon.  “Global warming is more disastrous to the agricultural industry of the Philippines and its neighboring Asian countries than in other parts of the world,” noted Dr. David Street of the US Argonne National Laboratory.
“As plant scientists refine their understanding of climate change — and the subtle ways in which plants respond — they are beginning to think that the most serious threats to agriculture will not be the most dramatic: a lethal heat wave or severe drought or endless deluge,” noted Nierenberg and Halweil.
“Instead, for plants that humans have bred for optimal climatic conditions, subtle shifts in temperatures and rainfall during key periods in the crop’s life will be most disruptive,” the two authors pointed out.
Plant scientists at the Philippine-based International Rice Research Institute (IRRI) are already noting regular heat damage in Cambodia, India, and their test farms in Laguna, where the average temperature is now 2.5 degrees Celsius higher than 50 years ago.
“In rice, wheat and maize, grain yields are likely to decline by 10% for every one degree (Celsius) increase over 30 degrees,” said researcher John Sheeny.  “We are already at or close to this threshold.”
According to Sheeny estimates, grain yields in the tropics might fall as much as 30% over the next 50 years — a period when the region’s already malnourished population will increase by 44%.
The Philippine Council for Agriculture, Forestry and Natural Resources Research and Development said that about 5-7 percent decline in yield of major crops in the country has been attributed to climate change. 
“The yield reduction is caused by heat stress, decrease in sink formation (number of spikelet per unit ground area), shortening of growing period, and increased maintenance for respiration,” said the line agency of the Department of Science and Technology.
Not too many know that emissions from burning oil, coal and gas are both heating up the oceans and making them more acidic. That is combining to reduce the amount of seafood that can be caught, according to “Ocean-Based Food Security Threatened in a High CO2 World.”
Seafood is a primary source of protein for more than a billion of the poorest people in the world, said Matthew Huelsenbeck, author of the report and marine scientist at Oceana, an environmental non-government organization.
“Seafood is the only source of protein in large parts of the world,” Huelsenbeck said.  “And for many local fishers, if they don’t catch fish, they go hungry.”
Filipinos are one of the world’s biggest fish consumers as more than half of their protein requirement come from fish.  Each year, a Filipino consumes almost 30 kilograms of seafood.
Rising sea levels are seen by many scientists as the most serious likely consequence of global warming. The Intergovernmental Panel on Climate Change (IPCC), a group of 2,500 scientists from all over the world, predicted in 2007 that sea levels will rise by up to 59 centimeters (23 inches) before 2100 due simply to the expansion of warmer ocean waters.
The Philippines ranks fourth in the Global Climate Risk Index. Fifteen of the 16 regions of the country are vulnerable to sea level rise.  The Philippine Country Study to Address Climate Change found that the Manila Bay is already subjected to several hazards, including flooding and storms.
Dr. Street said that most countries in Asia and the Pacific region have very large populations that are heavily dependent upon their marine ecosystems and natural resources.  Climate change will definitely make the problem more complicated.
“Many fish stocks will suffer because their spawning and nursery grounds in coastal mangroves and lagoons will be engulfed by rising sea levels,” the Panos Institute reported.  The IPCC said that climate change may become a more important threat to ocean fisheries than overfishing.
Then, there’s the connection between climate change and water. “In a warmer world, we will need more water – to drink and to irrigate crops,” said the London-based Panos Institute. “Water for agriculture is critical for food security,” points out Mark W. Rosegrant, a senior research fellow at the Washington-based International Food Policy Research Institute.
“The link between water and food is strong,” says Lester R. Brown, president of Earth Policy Institute, also based in Washington, D.C. “We drink, in one form or another, nearly 4 liters of water per day. But the food we consume each day requires at least 2,000 liters to produce, 500 times as much.”
This explains why 70 percent of all water use is for irrigation. An estimated 40 percent of agricultural products and 60 percent of the world’s grain are grown on irrigated land. “Agriculture is by far the biggest consumer of water worldwide,” IRRI said.
For instance, to raise a ton of rice, you need a thousand gallons of water.
“Climate change is the biggest environmental issue because it threatens to be disastrous,” pointed out Geird Leipold, international executive of Greenpeace.  “It will not only directly affect our climate.  It will severely affect human beings and the ecosystem.  We will have millions of people suffering from it.”