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Ancient Global Dimming Linked to Volcanic Eruption Ker Than for National Geographic NewsMarch 19, 2008 A "dry fog" that muted the sun's rays in A.D. 536 and plunged half the world into a famine-inducing chill was triggered by the eruption of a supervolcano, a new study says. The cause of the sixth-century global dimming has long been a matter of debate, but a team of international researchers recently discovered acidic sulphate molecules, which are signs of an eruption, in Greenland ice. This is the first physical evidence for the A.D. 536 event, which according to ancient texts from Mesoamerica, Europe,...

A researcher says he has a way to "Save the Earth from Global Warming" -- for a while, at least. The idea is to do what volcanoes do: inject material into the stratosphere. That would create a thin haze and reflect some sunlight. The general notion has been around for decades. But the paper proposes using it not as a permanent fix, but to buy time until greenhouse gases emissions can be brought under control. The proposal appears in the journal Science this week.

A new analysis by scientists at Scripps Institution of Oceanography at the University of California, San Diego, has produced surprising results showing how air pollution, global warming-producing greenhouse gases and natural fluctuations in the climate may have a range of significant consequences on the world's most populous region. [Snip] As the tropical Indian Ocean heats up due to greenhouse gases, the authors say, the northern Indian Ocean, which is adjacent to highly populated regions, is not warming as quickly as the rest of the ocean, resulting in increased drought conditions that could hold repercussions for more than 2 billion people...

Our planet's air has cleared up in the past decade or two, allowing more sunshine to reach the ground, say two studies in Science this week. Reductions in industrial emissions in many countries, along with the use of particulate filters for car exhausts and smoke stacks, seem to have reduced the amount of dirt in the atmosphere and made the sky more transparent. That sounds like very good news. But the researchers say that more solar energy arriving on the ground will also make the surface warmer, and this may add to the problems of global warming. More sunlight will...

We are all seeing rather less of the Sun, according to scientists who have been looking at five decades of sunlight measurements. They have reached the disturbing conclusion that the amount of solar energy reaching the Earth's surface has been gradually falling. Paradoxically, the decline in sunlight may mean that global warming is a far greater threat to society than previously thought. The effect was first spotted by Gerry Stanhill, an English scientist working in Israel. Cloud changes Comparing Israeli sunlight records from the 1950s with current ones, Dr Stanhill was astonished to find a large fall in solar radiation....

The Darkening Earth - Less sun at the Earth's surface complicates climate models By David Appell EARTHSHINE, the reflection of the earth on the unlit part of the moon, is one way to determine how much sunlight makes it to the surface of the earth. Brighter earthshine would suggest increasing cloudiness, which reflects sunlight away. Much to their surprise, scientists have found that less sunlight has been reaching the earth's surface in recent decades. The sun isn't going dark; rather clouds, air pollution and aerosols are getting in the way. Researchers are learning that the phenomenon can interact with global...

The World Is A Brighter Place WASHINGTON, May 28, 2004 Earthshine, the reflection from Earth, was determined by studying how much it illuminates the dark portion of the moon. Scientists studying the amount of light reflected by the Earth say the planet appeared to dim from 1984 to 2001 and then reversed its trend and brightened from 2001 to 2003. The change appears to have resulted from changes in the amount of clouds covering the planet. More clouds reflect more light back into space, potentially cooling the planet, while a dimmer planet with fewer clouds would be warmed by the...

<p>The Earth may be brightening.</p> <p>Scientists studying the amount of light reflected by the Earth say the planet appeared to dim from 1984 to 2001, and then reversed its trend and brightened from 2001 to 2003.</p> <p>The change appears to have resulted from changes in the amount of clouds covering the planet. More clouds reflect more light back into space, potentially cooling the planet, while a dimmer planet with fewer clouds would be warmed by the arriving sunlight.</p>

By RANDOLPH E. SCHMID Associated Press Writer May 27, 2004, 3:14 PM EDT WASHINGTON -- Scientists studying earthshine -- the amount of light reflected by the Earth -- say the planet appeared to dim from 1984 to 2001 and then reversed its trend and brightened from 2001 to 2003. The shift appears to have resulted from changes in the amount of clouds covering the planet. More clouds reflect more light back into space, potentially cooling the planet, while a dimmer planet with fewer clouds would be warmed by the arriving sunlight.

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...

Great! Now the news media have fears over global dimming to exploit. As reported by The Seattle Times, the earth's surface allegedly gets 15 percent less sunlight today than it did in the 1950s. Their methodology is dubious, but researchers say they have measured the decline of solar radiation at hundreds of sites and discerned dimming, a global-warming byproduct that partially counteracts it. This is fascinating stuff until you realize it's poppycock piled on balderdash. To understand the reason only requires one to know the basics of "the greenhouse effect." It begins when short-wave solar radiation, not impeded by "greenhouse...

'Global dimming' may stop the Earth overheating It's official: the world is getting darker. Scientists now agree that as cloud cover and particles in the atmosphere increase, the amount of radiation reaching us from the Sun is falling. And although they are nervous about raising the idea, they think the effect may help protect us from global warming.

Globe Grows Darker as Sunshine Diminishes 10% to 37% In the second half of the 20th century, the world became, quite literally, a darker place. Defying expectation and easy explanation, hundreds of instruments around the world recorded a drop in sunshine reaching the surface of Earth, as much as 10 percent from the late 1950's to the early 90's, or 2 percent to 3 percent a decade. In some regions like Asia, the United States and Europe, the drop was even steeper. In Hong Kong, sunlight decreased 37 percent.

In the second half of the 20th century, the world became, quite literally, a darker place. Defying expectation and easy explanation, hundreds of instruments around the world recorded a drop in sunshine reaching the surface of Earth, as much as 10 percent from the late 1950's to the early 90's, or 2 percent to 3 percent a decade. In some regions like Asia, the United States and Europe, the drop was even steeper. In Hong Kong, sunlight decreased 37 percent. No one is predicting that it may soon be night all day, and some scientists theorize that the skies have...

WASHINGTON - Scientists call it "global dimming," little-known trend that may be making the world darker than it used to be. Thanks to thicker clouds and growing air pollution, much of the Earth's surface is receiving about 15 percent less sunlight than it did 50 years ago, according to Michael Roderick, a climate researcher at Australian National University in Canberra. "Global dimming means that the transmission of sunlight through the atmosphere is decreasing," Roderick said. "Just look out the window when you fly into New York or to California - it's dimmer," said Beate Liepert, a climatologist at the Lamont-Doherty...

<p>Gerald Stanhill was reviewing solar radiation records in the late 1980s when he stumbled onto something that amazed him: Days were growing dimmer.</p> <p>"It was difficult to believe," said Stanhill, an Israeli government scientist. "So I started looking around for other continuous, long series of solar radiation measurements to make sure it wasn't an error."</p>

Each year less light reaches the surface of the Earth. No one is sure what's causing 'global dimming' - or what it means for the future. In fact most scientists have never heard of it. By David Adam In 1985, a geography researcher called Atsumu Ohmura at the Swiss Federal Institute of Technology got the shock of his life. As part of his studies into climate and atmospheric radiation, Ohmura was checking levels of sunlight recorded around Europe when he made an astonishing discovery. It was too dark. Compared to similar measurements recorded by his predecessors in the 1960s, Ohmura's...

Goodbye sunshine Each year less light reaches the surface of the Earth. No one is sure what's causing 'global dimming' - or what it means for the future. In fact most scientists have never heard of it. By David Adam Thursday December 18, 2003 The Guardian In 1985, a geography researcher called Atsumu Ohmura at the Swiss Federal Institute of Technology got the shock of his life. As part of his studies into climate and atmospheric radiation, Ohmura was checking levels of sunlight recorded around Europe when he made an astonishing discovery. It was too dark. Compared to similar measurements...