Greenery Spreading in Arctic

Global warming raises red flags in many corners, but for Howard Epstein, green is the color of concern.

Epstein, an associate professor of environmental sciences at U.Va., is on the cutting edge of climate research in  the Arctic. He co-authored a paper published in Science detailing how longer snow-free seasonsand extended growing periods combine to encourage the northward advance of trees, shrubs and other vegetation. Because plants absorb more heat than ice and snow, rather than reflecting solar radiation, the pattern could feed on itself if the trend continues.

Other researchers also have documented a decline in the extent of Arctic sea ice, and the two findings have raised alarms. "Any time you have these sorts of dramatic changes to the surface conditions of the planet, you have to start thinking about what’s going to happen next," he says. "This is significant because conditions in the Arctic affect global atmospheric conditions. The Arctic is dominated by snow and ice; if this condition were to change, even subtly, there is potential for further change to the global climate."

What’s happening next for Epstein is a study, funded by the National Science Foundation, called "The Greening of the Arctic." Researchers will examine whether there are links between what’s occurring with sea ice and trends in the terrestrial environment.

"We’re trying to connect the dots," Epstein says.

Play It Safe: Keep Babies Facing Rearward

When it comes to safety in vehicles, forward-thinking parents should keep their children longer in rear-facing seats.

That’s a conclusion reached by Chris Sherwood (Engr ’91) and colleagues at U.Va.’s Center for Applied Biomechanics.

Parents have long been told that children are ready to move from rear-facing to forward-facing seats if they have reached 20 pounds in weight and 1 year in age.

Sherwood, a research scientist at the center, studied 870 children under the age of 2 who had been in car accidents. He found that those in forward-facing seats were more than four times as likely to be injured in side crashes as toddlers in rear-facing seats. In frontal crashes, which tend to be less serious, the benefit was not statistically significant.

Sherwood presented the preliminary findings—which are undergoing peer review before being published—at an American Academy of Pediatrics meeting.

Sherwood says it’s common in Scandinavian countries for children to be in rear-facing seats up to 3 or 4 years old. Many rear-facing seats already on the market can be used for older, larger children, at least up to 30 pounds.

Many parents feel social pressure to switch the child’s position. "But 1-year-olds who have been in rear-facing seats don’t know any difference," Sherwood says.

In the Zone

As you dig in at the plate, you’re feeling good. You smoked a couple of line drives into left field in your first two at-bats, and your confidence is up. You take a few practice swings and focus on the pitcher’s arm. Here comes the pitch. Oooh, the ball looks so big …

Athletes in many sports report similar violations of physical laws. Basketball hoops and golf holes seem to widen to swallow the ball; tennis balls travel in slow motion as you line up the return; running backs see the smallest gaps between linemen as interstate highways.

In those cases, perception is reality, says Jessica Witt (Grad ’03), a doctoral student in cognitive psychology who, along with adviser and co-author Dennis Proffitt, published a fascinating study in the December issue of Psychological Science.

Stationed alongside Charlottesville-area softball fields, Witt used cups of Gatorade to lure players whose games had just concluded. Holding up a poster depicting circles of eight different diameters, she asked them to point to the one closest to the size of the softball they had just played with, then asked about their hitting in the previous game.

The findings: on average, the more hits players had, the more likely they were to choose a bigger circle. "It’s not that they think it is bigger—it is bigger," Witt says. "In our lab, perception is reality as it relates to you."