Weaker sun will not delay global warming: study

 A weaker sun over the next 90 years is not likely to significantly delay a rise in global temperature caused by greenhouse gases, a report said Monday.

The study, by Britain's Meteorological Office and the university of Reading, found that the Sun's output would decrease up until 2100 but this would only lead to a fall in global temperatures of 0.08 degrees Celsius.

Scientists have warned that more extreme weather is likely across the globe this century as the Earth's climate warms.

The world is expected to heat up by over 2 degrees Celsius this century due to increased greenhouse gas emissions.

Current global pledges to cut carbon dioxide and other greenhouse gas emissions are not seen as sufficient to stop the planet heating up beyond 2 degrees, a threshold scientists say risks an unstable climate in which weather extremes are common.

"This research shows that the most likely change in the sun's output will not have a big impact on global temperatures or do much to slow the warming we expect from greenhouse gases," said Gareth Jones, climate change detection scientist at the Met Office.

"It's important to note this study is based on a single climate model, rather than multiple models which would capture more of the uncertainties in the climate system," he added.

During the 20th century, solar activity increased to a maximum level and recent studies have suggested this level of activity has reached, or is nearing, an end.

The scientists used this maximum level as a starting point to project possible changes in the sun's activity over this century.

The study also showed that if the sun's output went below a threshold reached between 1645 and 1715 - called the Maunder Minimum when solar activity was at its lowest observed level - global temperature would fall by 0.13 degrees Celsius.

"The most likely scenario is that we'll see an overall reduction of the sun's activity compared to the 20th Century, such that solar outputs drop to the values of the Dalton Minimum (around 1820)," said Mike Lockwood, solar studies expert at the university of Reading.

"The probability of activity dropping as low as the Maunder Minimum - or indeed returning to the high activity of the 20th Century - is about 8 percent."

Kepler telescope team finds 11 new solar systems

NASA's planet-hunting Kepler space telescope has found 11 new planetary systems, including one with five planets all orbiting closer to their parent star than Mercury circles the Sun, scientists said on Thursday.

The discoveries boost the list of confirmed extra-solar planets to 729, including 60 credited to the Kepler team. The telescope, launched in space in March 2009, can detect slight but regular dips in the amount of light coming from stars. Scientists can then determine if the changes are caused by orbiting planets passing by, relative to Kepler's view.

Kepler scientists have another 2,300 candidate planets awaiting additional confirmation.

None of the newly discovered planetary systems are like our solar system, though Kepler-33, a star that is older and bigger than the Sun, comes close in terms of sheer numbers. It has five planets, compared to our solar system's eight, but the quintet all fly closer to their parent star than Mercury orbits the Sun.

The planets range in size from about 1.5 times the diameter of Earth to five times Earth's diameter. Scientists have not yet determined if any are solid rocky bodies like Earth, Venus, Mars and Mercury or if they are filled with gas like Jupiter, Saturn, Uranus and Neptune.

The Kepler team previously found one star with six confirmed planets and a second system with five planets, said planetary scientist Jack Lissauer, with NASA's Ames Research Center in Moffett Field, California.

Nine of the new systems contain two planets and one has three, bringing the total number of newly discovered planets to 26. All are closer to their host stars than Venus is to the Sun.

"This has tripled the number of stars which we know have more than one transiting planet, so that's the big deal here," Lissauer told Reuters.

"We're starting to think in terms of planetary systems as opposed to just planets: Do they all tend to have similar sizes? What's the spacing? Is the solar system unusual in those regards?" he said.

Kepler is monitoring more than 150,000 stars in the constellations Cygnus and Lyra.

The research is published in four different papers in Astrophysical Journal and the Monthly Notices of the Royal Astronomical Society.

Snowy owls soar south from Arctic in rare mass migration

 Bird enthusiasts are reporting rising numbers of snowy owls 

from the Arctic winging into the lower 48 states this winter in a 

mass southern migration that a leading owl researcher called 

"unbelievable."

Thousands of the snow-white birds, which stand 2 feet tall with 5-foot wingspans, have been spotted from coast to coast, feeding in farmlands in Idaho, roosting on rooftops in Montana, gliding over golf courses in Missouri and soaring over shorelines in Massachusetts.

A certain number of the iconic owls fly south from their Arctic breeding grounds each winter but rarely do so many venture so far away even amid large-scale, periodic southern migrations known as irruptions.

"What we're seeing now -- it's unbelievable," said Denver Holt, head of the Owl Research Institute in Montana.

"This is the most significant wildlife event in decades," added Holt, who has studied snowy owls in their Arctic tundra ecosystem for two decades.

Holt and other owl experts say the phenomenon is likely linked to lemmings, a rodent that accounts for 90 percent of the diet of snowy owls during breeding months that stretch from May into September. The largely nocturnal birds also prey on a host of other animals, from voles to geese.

An especially plentiful supply of lemmings last season likely led to a population boom among owls that resulted in each breeding pair hatching as many as seven offspring. That compares to a typical clutch size of no more than two, Holt said.

Greater competition this year for food in the Far North by the booming bird population may have then driven mostly younger, male owls much farther south than normal.

Research on the animals is scarce because of the remoteness and extreme conditions of the terrain the owls occupy, including northern Russia and Scandinavia, he said.

The surge in snowy owl sightings has brought birders flocking from Texas, Arizona and Utah to the Northern Rockies and Pacific Northwest, pouring tourist dollars into local economies and crowding parks and wildlife areas. The irruption has triggered widespread public fascination that appears to span ages and interests.

"For the last couple months, every other visitor asks if we've seen a snowy owl today," said Frances Tanaka, a volunteer for the Nisqually National Wildlife Refuge northeast of Olympia, Washington.

But accounts of emaciated owls at some sites -- including a food-starved bird that dropped dead in a farmer's field in Wisconsin -- suggest the migration has a darker side. And Holt said an owl that landed at an airport in Hawaii in November was shot and killed to avoid collisions with planes.

He said snowy owl populations are believed to be in an overall decline, possibly because a changing climate has lessened the abundance of vegetation like grasses that lemmings rely on.

This winter's snowy owl outbreak, with multiple sightings as far south as Oklahoma, remains largely a mystery of nature.

A snowy white owl takes flight in this undated handout photo courtesy of U.S. Fish & Wildlife Service. Bird enthusiasts are reporting rising numbers of snowy owls from the Arctic winging into the lower 48 states this winter in a mass southern migration that a leading owl researcher called "unbelievable" according to Denver Holt, head of Owl Research Institute in Montana. REUTERS/U.S. Fish&Wildlife Service/Handout