Agriculture
Chicken Eggs as Drug Factories
Where Have All the Bees Gone?
New Gene Fights Potato Blight
Amphibians
Toads
Poison Dart Frogs
Salamanders and Newts
Animals
Insect Stowaways
Hot Pepper, Hot Spider
Little Bee Brains That Could
Behavior
Training Your Brain to Feel Less Pain
GSAT Mathematics Quiz, Teaching Math, teaching anxiety
Surprise Visitor
Birds
Penguins
Geese
Robins
Chemistry and Materials
Picture the Smell
Butterfly Wings and Waterproof Coats
Popping to Perfection
Computers
Galaxies far, far, far away
Graphene's superstrength
Galaxies on the go
Dinosaurs and Fossils
An Ancient Feathered Biplane
Have shell, will travel
Early Birds Ready to Rumble
E Learning Jamaica
Results of GSAT are in schools this week
E Learning in Jamaica WIN PRIZES and try our Fun Animated Games
2014 GSAT Results for Jamaican Kids
Earth
Drilling Deep for Fuel
Undersea Vent System Active for Ages
Snowflakes and Avalanches
Environment
Bald Eagles Forever
Alien Invasions
Shrimpy Invaders
Finding the Past
Untangling Human Origins
Sahara Cemetery
Salt and Early Civilization
Fish
Seahorses
Piranha
Electric Eel
Food and Nutrition
Chew for Health
A Taste for Cheese
Packing Fat
GSAT English Rules
Who vs. That vs. Which
Pronouns
Subject and Verb Agreement
GSAT Exam Preparation Jamaica
GSAT Practice Papers | GSAT Mathematics | Maths
Ministry of Education Announces 82 GSAT Scholarships for 2010
10 Common Mistakes When Preparing for the GSAT Math Test
GSAT Exams Jamaica Scholarships
GSAT Exam Preparation
GSAT Scholarship
GSAT stars reap scholarship glory
GSAT Mathematics
GSAT Mathematics Quiz, Teaching Math, teaching anxiety
Losing with Heads or Tails
Prime Time for Cicadas
Human Body
Heart Revival
A Long Trek to Asia
Running with Sneaker Science
Invertebrates
Scorpions
Beetles
Invertebrates
Mammals
Raccoons
Weasels
African Jackal
Parents
Raise a Lifelong Reader by Reading Aloud
How children learn
Children and Media
Physics
Echoes of a Stretched Egg
Spin, Splat, and Scramble
Extra Strings for New Sounds
Plants
A Change in Leaf Color
Surprise Visitor
Springing forward
Reptiles
Gila Monsters
Alligators
Box Turtles
Space and Astronomy
Slip-sliding away
Dark Galaxy
Planets on the Edge
Technology and Engineering
Shape Shifting
Squeezing Oil from Old Wells
A Light Delay
The Parts of Speech
What is a Noun
Pronouns
Countable and Uncountable Nouns
Transportation
Seen on the Science Fair Scene
How to Fly Like a Bat
Troubles with Hubble
Weather
The solar system's biggest junkyard
Weekend Weather Really Is Different
Where rivers run uphill
Add your Article

Watering the Air

The average temperature around the world is rising. People living in the U.S. Midwest might find this fact hard to believe, though. Two new studies show that in America’s heartland, summers are now cooler and wetter than they were in years past. The scientists suggest that the change in the Midwest climate may have happened because of farming.

The first study was led by David Changnon, a climatologist at Northern Illinois University in DeKalb. He presented one of the studies in January during a meeting of scientists who study weather and climate. A climatologist studies the climate of an area, which includes measuring rainfall, temperature and wind. Climatologists want to know how these factors have changed in the past, and how they’ll change in the future.

Changnon and his team studied temperature records from Chicago and 13 other sites in the Midwest. They found that since 1970, the average temperature in Illinois and Iowa during July and August has gone down — by up to one degree Fahrenheit — from what it was during the years between 1930 and 1969. Their investigation also showed that the average rainfall in those two states during those two months has increased. Between 1970 and 2009, about 0.33 inches more rain fell than between 1930 and 1969.

These two changes — lower temperatures and more rainfall — may be connected by humidity, Changnon says. Humidity is the measure of how much moisture is in the air. Humid air, which contains a lot of moisture, takes longer to heat up than dry air, Changnon notes. And humid air often releases its moisture through rainfall.

So where did the extra moisture in the air come from? Changnon points to farms in the region. As plants grow, they pull moisture from the ground and release it into the air. And among plants, soybean and corn plants release a lot of moisture. Midwestern farms now plant more soybeans and corn than in the past, with 97 percent of farmland today planted with these two crops. In the 1930s, corn and soybeans covered only about 57 percent, Changnon says. He also notes that the plants are planted closer together now than they used to be, so there are more plants per acre than in the past.

The second study, like Changnon’s, also found an increase in rainfall in the same area. But it points to another possible source for the increased moisture. Alan Robock of the Center for Environmental Prediction at Rutgers University in New Brunswick, N.J., was part of the team that produced the second study and presented the group’s findings at the same meeting as Changnon. The group includes Ying Fan, who led the study, and Anthony DeAngelis, M. D. Kustu and D. A. Robinson, all from Rutgers University.

The team found that irrigation practices in the Great Plains have changed over the years. (Irrigation is how farmers get water to crops, especially crops far from a river or other body of water. Irrigation is a way of bringing water to those crops all the time.) The researchers studied a vast area of the United States that stretches from South Dakota to Oklahoma and the Texas panhandle. They found that in 1930, farmers in that region irrigated only about 1.8 million acres of farmland, an amount roughly half the size of Connecticut. In 1980, however, farmers irrigated nearly 15 million acres — more land than Vermont and New Hampshire combined.

Much of this irrigation uses water from natural reservoirs, such as those that are underground. Plants use the water and then release it into the air, so irrigating more and more plants means that more and more water makes it into the air. Robock suspects that as farms in the Great Plains received more irrigation, they released more moisture into the air — which then was carried downwind to the Midwest, where it caused more rain.

These results by Changnon and Robock and his colleagues are the first step toward understanding a change in the weather. But it will take more studies before crop irrigation can definitely be blamed for changes in temperature and rainfall.

Watering the Air
Watering the Air








Designed and Powered by HBJamaica.com™