Sun on the run? Not in the Northwest

Register Guard ^ | 5/17/04 | Greg Bolt

[ZGuy]

Global warming may be drawing the solar shades on some parts of the world, but the sun is shining brighter than ever in the Pacific Northwest.

Solar energy researcher Frank Vignola at the University of Oregon says he's documented a 10 percent increase in the amount of sunlight shining on the Northwest over the past 10 years. That runs counter to recent findings that suggest that rising pollution has spurred a "global dimming" that has cut sunlight worldwide during the latter half of the 20th century.

"We've seen the (sunlight) slowly but surely increase," said Vignola, who directs the UO's Solar Radiation Monitoring Laboratory. "2002 was the sunniest year, particularly in Eugene, that we've had on record in the last 25 years."

Vignola said he's skeptical about the data that led some scientists to suggest the global dimming theory, saying they don't seem to have enough data from reliable instruments to spot a trend. He has data from more reliable instruments, but he only has long-term data from three monitoring stations and partial data from a fourth.

In the end, it's probably too soon for anyone to say whether the Earth is getting sunnier or cloudier. But Vignola said his measurements show that in the here and now, the upper left-hand corner of America is awash in sunlight.

He bases that on data collected over 25 years at stations in Eugene, Burns and Hermiston and over a shorter time in Twin Falls, Idaho. According to Vignola, instruments at those stations are calibrated and cleaned weekly, while the data cited by global dimming theorists comes from apparatus that does not get regular attention or measure as accurately.

"I'm pretty skeptical (of the dimming theory) because of the difficulty in getting high-quality, long-term measurements," he said. "Something can be happening locally, to be sure, but I think the amount they're reporting seems a little high."

The problem is, no one really has conclusive data. Professor James Coakley of the College of Atmospheric and Oceanic Sciences at Oregon State University said so few people are doing research on surface sunlight that it's impossible to spot a trend.

Coakley, whose research focuses on cloud formation and global warming, said the proposition that rising pollution levels are causing more sunlight to be reflected back into space is a sound one. But he said the data to prove it's causing global dimming just isn't there yet.

"Actually seeing a trend that's a valid trend is a difficult thing to do," he said. "It's very difficult to find evidence that it's happening globally."

State climatologist George Taylor echoed that assess- ment.

The dynamics that go into creating long-term climate trends are so labyrinthine that there's no way to know whether it's time to invest in sun lamps or sunscreen.

"It's so complex that I think it's hard to come up with a simple answer here," he said. "We don't have this thing figured out."

[Chad Fairbanks]

"Natural light! Get it off me! GET IT OFF ME!"

[LiteKeeper]

Anti-junkscience

[talleyman]

The increase in sunlight is most noticeable during the day...