Hot, Cold, Wet, Dry: When Weather Becomes Climate

7/27/2010

The past as prologue: fortune-telling from tree rings; The Green Revolution hits the skids: genetically resilient pathogens and monoculture crops

What happens when the future comes early? When does record-breaking weather segue from unfortunate inconvenience to an inconvenient truth?

When…

China reports massive floods affecting 75% of its provinces? The tally of dead and missing now tops 1,000, with the devastation said to affect 110 million people. 645,000 homes have been destroyed. The economic hit is estimated to at $21 billion – and rising. Or…

Russia has a drought like it hasn’t seen in 130 years? The country’s breadbasket is toast: 20% of the wheat crop is lost at a financial cost that could easily exceed $1 billion.Wildfires have consumed hundreds of square miles. In Moscow, lack of air conditioning and love of liquor has led to thousands of “swimming while drunk” deaths. (update 8/8/10:Peat fires send Moscow pollution levels soaring, a third of the wheat crop lost, exports temporarily banned) (update 8/10/10: Russians defend nuclear sites from fires) Or…

Argentina and Uruguay shiver in below freezing temperatures? Hypothermia in the streets of Buenos Aires and snow reported in seaside resort town. (update 8/6/10: Chilly in Chile, 6 million freshwater fish freeze in Bolivia, snow in Brazil and Argentina, avocado, lemon, orange crops decimated) Or…

the Rio Grande actually looks like a big raging river? Some sections along the U.S. / Mexican border have risen 17 feet and more above flood stage, cutting off clean water supplies, affecting tens of thousands of people, destroying thousands of homes and triggering mass evacuations. Or…

Pakistan and Afghanistan are devasted by record monsoon rains, causing hundreds of deaths? More than three million people affected, according to U.N. estimates, including 1.4 million children. Large areas of farmland destroyed and unprecedented flooding. (update: 8/8/10: Over 1,000 deaths, 12 million affected, damage worse than 2005 earthquake) (update 8/10/10: 14 million affected, thousands of villages wiped out, hundreds of kilometers of roads and bridges) (update 8/14/10: 20 million affected, 1,600 dead, tens of thousands at risk for cholera) Or…

NOAA reports the planet has steadily been growing warmer for the last 50 years and that 2010 is on track to becoming the hottest year on record? For the last 304 months (a little over 25 years), the average monthly global temperatures have exceed the average for entire 2oth century. This past June was the hottest on record.

“Warmer than average global temperatures have become the new normal,” says Jay Lawrimore, chief of climate analysis at NOAA’s National Climatic Data Center, which tracks these numbers. “The global temperature has increased more than 1 degree Fahrenheit [0.7 degree C] since 1900 and the rate of warming since the late 1970s has been about three times greater than the century-scale trend.”…

…”Frankly, I was expecting that we’d see large temperature increases later this century with higher greenhouse gas levels and global warming,” Stanford climate scientist Noah Diffenbaugh, who headed up the research, said in a prepared statement. “I did not expect to see anything this large within the next three decades.”

Was last Spring’s Nashville flood, which took the region by surprise after 13 inches of rain fell in 24 hours, a local catastrophe or part of much larger trend? What about the 8 inch deluge than drowned Milwaukee last week? Or the second tornado ever to hit the Bronx?

WEATHER HAPPENS / CLIMATES CHANGE
If man-made greenhouse gases are behind the deadly weather, that’s good news: We can still do something about it. But as a new study of historic droughts in Asia shows, the ramifications of disturbed weather patterns can be devastating, no matter what the cause.

Scientists at Columbia University’s Lamont-Doherty Earth Observatory spent 15 years collecting samples from more than 300 sites across Asia to create an atlas of tree ring data for monsoon weather patterns. The correlations between major droughts and political unrest are striking, if not completely surprising. From the collapse of the Khmer civilization to the demise of the Ming Dynasty and the French Revolution, nothing topples a government faster than a desperate hungry mob.

Perhaps the worst drought, the scientists found, was the Victorian-era “Great Drought” of 1876-1878. The effects were felt across the tropics; by some estimates, resulting famines killed up to 30 million people. According to the tree-ring evidence, the effects were especially acute in India, but extended as far away as China and present-day Indonesia. Colonial-era policies left regional societies ill-equipped to deal with the drought’s consequences, as historian Mike Davis details in his book Late Victorian Holocausts. Famine and cholera outbreaks at this time in colonial Vietnam fueled a peasant revolt against the French.

The political opposition to the now crippled U.S. Climate Bill should be quaking in their boots. Given the staggering amount of scientific evidence linking human-generated greenhouse gas emissions to global warming and climate change, they will bear the blame for blocking action when it could have made a difference. (According to a new survey published in the Proceedings of the National Academy of Sciences, 97% of scientists say climate change “very likely” has a man-made component.)

A BOUNTY OF BLIGHTS: CAUSE & EFFECT OR COINCIDENCE?The cruelty of blight is uniquely insidious. Hopes, dreams and futures are destroyed along with crops. A blight is promise snatched away. In a matter of weeks, sometimes days, sometime hours, months of labor is laid to waste and investment is turned to debt.

It doesn’t take much: just a few invisible spores carried by the wind to a host plant. Once a botanical beach-head is established, blights – which thrive in the monocultures of modern agriculture – quickly become “community diseases,” spreading from plant to plant, field to field, region to region, painting once verdant fields black with the brush of death.

The first major victory in the The Green Revolution was genetic lab-tweak that made wheat impervious to a blight called stem rust, while also increasing yields – a rare and remarkable “two-fer” benefit. So significant was this breakthrough, plant biologistNorman Borlaug was award the Nobel Prize for it. The dream of eradicating hunger seemed within reach. Yet a little over a half-century later, the solution – crop protection provided by a single gene – has become part of the problem.

In 1999, a strain of rust was discovered in a wheat field in Uganda that had evolved past the genetic barrier. Dubbed “Ug99,” it has since splintered off into several strains or “races,” some of which are impervious to more recently developed multi-gene defenses. In a little over a decade, stem rust has traveled 5,000 miles and now threatens grain production in Africa and Asia, and indirectly threatens production everywhere else. From the pathogen’s perspective, all wheat has become more or less alike as diversity has been systematically bred away.

Wheat is the primary source of calories for millions of people worldwide, and accounts for around 30 percent of global grain production and 44 percent of cereals used as food. Globally, wheat provides nearly 55 percent of the carbohydrates and 20 percent of the food calories we consume every day.

- Dr. Mahmoud Solh, Director General of the Syria-based International Center for Agricultural Research in the Dry Areas (ICARDA).

With so much at stake, an international collaborative effort, spearheaded by the Borlaug Global Rust Initiative, is playing a frantic game of defense, developing resistant strains to deploy strategically as barriers to slow the blight’s spread. But the work requires the cooperation of countries otherwise at odds, such as India and Pakistan. And it takes money: steady, dependable funding and lots of it.

Stem rust isn’t the only globetrotting super-pathogen:

An especially aggressive strain of brown streak virus is attacking Cassava, a staple for 800 million people in Africa, Asia and South America. In the 6 years since it was first spotted in East Africa, it has spread at pandemic speed. Cassava, a drought-tolerant plant that requires very little tending, is particularly important for regions beset with malaria and HIV/AIDS. Its loss means billions of dollars more needed for basic food aid. Cassava is also under siege from mealybugs in Thailand, which produces 60% of the world exports. Last year, many farmers suffered lost their entire crop.

Late blight, a.k.a. the blight that caused Ireland’s Great Potato Famine, turns out to also have a taste for American tomatoes. Last year, its spores not only rode the wind, but took to the highways, hitching on seedling plants trucked to home improvement stores across the country. In only two years, it appears to have become entrenched.

Stripe rust, another wheat plague, was recently discovered to have an alternate host, the common ornamental barberry plant, on which the fungus sexually reproduces. The resulting genetic diversity of the fungus, set against the genetic uniformity of wheat, supplies the resilience that has made it so difficult to stamp out.

A warming world favors pathogens’ survival over winter, while shifting weather patterns can blow them into new territories. Human-mediated transport (trade and travel) clearly play a large role as well.

Whatever the drivers, these colliding trends of record-breaking weather / climate change and emerging plant diseases spell big trouble for global food security. In just the past month, wheat prices spiked 30%, due mostly to the Russian drought. Russia will still have enough for domestic needs, but higher prices are expected to drive up inflation, and there will be that much less for export. Stem rust primarily affects small farmers gowing for local consumption in the developing countries. Higher global commodity prices also translates into higher food aid costs.

According to the scientists at NOAA, the extreme weather of 2010 may very well be the “new normal.” Hotter, colder, wetter, drier. And way beyond inconvenient.

FURTHER READING