The Long View

April 1, 2014 09:11 PM
 
TP 048 T14103

Long-range weather forecast offers fresh insight

The local 10-day forecast remains one of the cheapest, most accessible—and yet most valuable—resources at your disposal. Look it up any time online, or wait until the 10 p.m. news and the meteorologist will talk you through it.

Increasingly, farmers are tapping into longer-range forecasts and broadening their understanding of climate change to find new advantageous production practices.

Consider this: A century ago, farmers planted the nation’s corn crop about 21 days later than they do today, give or take a few days depending on exact geography. So while year-over-year changes are sometimes imperceptible, they can and do add up over time.

"Not all impacts of climate change are negative," says Linda Prokopy, an associate professor at Purdue University and project lead for Useful to Usable (U2U). The five-year integrated research and Extension project is funded by USDA and comprised of nine university partners working together to develop climate and forecasting tools for farmers. 

So far, the group has developed AgClimate View and the Corn Growing Degree Day decision support tool, which allows users to track a blend of customizable real-time and historical data to help them make smarter decisions from planting to harvest. Several other inter-active tools are in development as well, Prokopy says.

"A lot of farmers want to make decisions based on longer-term climate influences, and ultimately, we want to develop tools farmers can use for these decisions," she says.

Advanced Notice. January’s polar vortex, which descended on much of the continental U.S., was a brutish shock to most people. But historical climatologist Evelyn Browning-Garriss had been patiently waiting for it to arrive months in advance. That’s because the unusu­ally cold Arctic summer built up a payload of super cold air that it dished out this winter.

"It didn’t take rocket science to see this would happen, but it would’ve been helpful for people to know so they could’ve properly prepare for it," she says.

Browning-Garriss says that longer-term forecasts can help farmers make any number of production decisions months in advance, from optimal planting date to hybrid selection and in-season inputs.

Like so many other things, climate forecasting noise can be sharpened into a useful signal if it’s approached in a certain manner, explains Al Dutcher, state climatologist at the University of Nebraska–Lincoln.

"As planting season nears, a plethora of weather experts will be commenting on how this year’s weather will affect U.S. ag production," he says. "If you approach weather prediction as a risk-analysis tool, you can eliminate much of this banter as simply information overload."

Dutcher looks for several signals within the noise, such as soil moisture recharge and Rocky Mountain snowpack, that can show where drought susceptibility could be on the rise (or in decline) prior to a given production region. 

"For example, snowpack is impressive in the central and northern Rockies, which should support more frequent thunderstorm development in the western High Plains through the first half of the summer," he says.

Also, prior research has shown that two oceanic weather patterns in parti­cular, the Pacific Decadal Oscill­ation (PDO) and the Atlantic Multi­decadal Oscillation (AMO), correlate to drought risk. The worst-case scenario is when the Pacific Ocean is cooler than normal and the Atlantic is warmer than normal. The last time this happened was 2012, when much of the country suffered from severe drought.

In the best-case scenario, the opposite is true—the Pacific Ocean is warmer than normal, while the Atlantic Ocean is cooler than normal. That makes current weather patterns appear favorable for U.S. agriculture, Dutcher says.

"It appears the Pacific Ocean is beginning to signal a movement toward the warm phase, while the Atlantic is beginning to show signs of entering a cold phase," he says.

Dutcher adds that these weather analyses shouldn’t be taken as a cause-effect relationship that a given event will occur; rather, the odds of the event become more or less favorable based on the phase of the PDO and AMO. Farmers can use those odds to better calculate risk on their operations, he says.

"If your drought risk increases, the effect could be partially offset by above-normal soil moisture recharge," Dutcher explains. "However, if your soil moisture recharge is below normal and your drought risk is high, you might want to take defensive positions to protect your farm income stream."
TP 049 T14103

The Months Ahead. So what weather might be in store for this year’s planting season? Browning-Garriss says the Atlantic Ocean could potentially deliver a volatile, wet spring, particularly in the Ohio River Valley, when it slams up against the frigid air it’s experiencing now. 

"Two air masses will crash, and like any crash, it gets messy," she says.

Climatologists are on the lookout for the possible emergence of an El Niño cycle.

"Many models are now predicting a weak El Niño, with El Niño conditions beginning in the summer," Browning-Garriss says. "This would be great for U.S. grains, fruits and vegetables, and overall for world crops. An El Niño has the potential to break the California drought, which could be the light at the end of the tunnel."

The National Weather Service Climate Prediction Center issued an "El Niño Watch" in early March, giving a 50-50 shot of it developing this summer or fall. Depending on its strength, Californians will certainly welcome the wet weather it could bring, and the Midwest could enjoy a milder winter in 2014/15, but other parts of the world (most notably Australia) would fall into severe drought.

Even if spring conditions are favorable, farmers—espe­cially in the upper Midwest—still have one environmental factor that could delay planting: frost. This frigid winter has pushed frost as deep as 3' in Iowa and even deeper in Minnesota and the Dakotas.

"Soils can lose that frost fast with the higher solar angle," Dutcher says. "Even if the soils thaw rapidly, it will take additional time to get the soil root zone warm enough to trigger plants and trees to break dormancy."


The bottom line: Different weather scenarios pack various in-field challenges and marketing opportunities, so it pays to take the long view when tracking weather and climate. 


For a short-term glimpse of weekly weather forecasts, visit the AgWeb weather section at www.agweb.com/weather

 

Back to news

Comments

 

Rate this News Article:

Spell Check

No comments have been posted to this News Article

Close