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Source: University Of California - Berkeley Date: 2004-06-03 17th Century Solar Oddity Believed Linked To Global Cooling Is Rare Among Nearby Stars Berkeley - A mysterious 17th century solar funk that some have linked to Europe's Little Ice Age and to global climate change, becomes even more of an enigma as a result of new observations by University of California, Berkeley, astronomers. For 70 years, from 1645 until 1714, early astronomers reported almost no sunspot activity. The number of sunspots - cooler areas on the sun that appear dark against the brighter surroundings - dropped a thousandfold, according to some...

Ice cores unlock climate secrets By Julianna Kettlewell BBC News Online science staff Tiny bubbles of ancient air are locked in the ice Global climate patterns stretching back 740,000 years have been confirmed by a three kilometre long ice core drilled from the Antarctic, Nature reports. Analysis of the ice proves our planet has had eight Ice Ages during that period, punctuated by rather brief warm spells - one of which we enjoy today. If past patterns are followed in the future, we can expect our "mild snap" to last another 15,000 years. The data may also help predict how...

PARIS (AFP) - The North Pole once had a balmy, sub-tropical sea because of extreme global warming, according to European scientists who have carried out the world's deepest drilling into ancient sediment on the far northern seabed. Cores retrieved from up to 430 metres (1,397 feet) below the seafloor in waters 1,300 metres (4,550 feet) deep show that, for a brief period which occurred around 55 million years ago, the Arctic Ocean was around 20 C (68 F), compared with today's typical average temperature of minus 1.5 C (29.3 F), they said on Tuesday. "It occurred during a period called...

If you are the kind of person who worries about the future, this might not make happy reading.Scientists have found that on average mammal species enjoy only 2.5 million years of life before being wiped out because of the Earth's "wobble." They say when the tilt and orbit reach key points it can spark dramatic global cooling - and the last time this happened was 2.6 million years ago. This suggests we are overdue a wave of extinction. However, before you panic, scientists say our planet has changed beyond all recognition in the last 3 million years. The new research...

More Sci-Fi reading for your summer weekend: Javed Ikbal writes "Decipher by Stel Pavlou is a mind-blowing work of science fiction. If you thought Stephenson's Snowcrash did a great job of bringing myth and science together, bite into this. I am still shaking my head over the amount of research that must have gone into this book." Read on for Javed's review. Warning -- spoilers within. What it's about: Tag line: Mankind had 12,000 years to decipher the message. We have one week left ... Let me make something clear. Although this is my first Slashdot review, I do not...

comet crashing into the Earth some 13,000 years ago was thought to have spelled doom to a group of early North American people, and possibly the extinction of ice age beasts in the region. But the space rock was wrongly accused, according to a group of 16 scientists in fields ranging from archaeology to crystallography to physics, who have offered counterevidence to the existence of such a collision. Almost 13,000 years ago, a prehistoric Paleo-Indian group known as the Clovis culture suffered its demise at the same time the region underwent significant climate cooling known as the Younger Dryas. Animals...

Central Mexico’s Lake Cuitzeo contains melted rock formations and nanodiamonds that suggest a comet impacted Earth around 12,900 years ago, scientists say. CREDIT: Israde et al. (2012) New evidence supports the idea that a huge space rock collided with our planet about 13,000 years ago and broke up in Earth's atmosphere, a new study suggests. This impact would have been powerful enough to melt the ground, and could have killed off many large mammals and humans. It may even have set off a period of unusual cold called the Younger Dryas that began at that time, researchers say. The...

Posted on June 16, 2012 by Anthony Watts WUWT readers may recall this recent story: New evidence of Younger Dryas extraterrestrial impact The story below provides much more detail about the Younger Dryas event and the split that has developed in the scientific community over the cause. I’ve added this graph below from NCDC to give readers a sense of time and magnitude of the event. – Anthony The Younger Dryas cold interval as viewed from central Greenland. From:Quaternary Science Reviews Volume 19, Issues 1-5, 1 January 2000, Richard B. AlleyGuest Post By: Rodney Chilton www.bcclimate.com A consideration of many...

This is a follow up posting to Younger Dryas -The Rest of the Story!Guest post by Don J. Easterbrook Dept. of Geology, Western Washington University.The Younger Dryas was a period of rapid cooling in the late Pleistocene 12,800 to 11,500 calendar years ago. It followed closely on the heels of a dramatically abrupt warming that brought the last Ice Age to a close (17,500 calendar years ago), lasted for about 1,300 years, then ended as abruptly as it started. The cause of these remarkably sudden climate changes has puzzled geologists and climatologists for decades and despite much effort to find...

Scientists, it's said, behave more like lawyers than philosophers. They do not so much test their theories as prosecute their cases, seeking supportive evidence and ignoring data that do not fit—a failing known as confirmation bias. They then accuse their opponents of doing the same thing. This is what makes debates over nature and nurture, dietary fat and climate change so polarized. But just because the prosecutor is biased in favor of his case does not mean the defendant is innocent. Sometimes biased advocates are right. An example of this phenomenon is now being played out in geology over the...

We report the discovery in Lake Cuitzeo in central Mexico of a black, carbon-rich, lacustrine layer, containing nanodiamonds, microspherules, and other unusual materials that date to the early Younger Dryas and are interpreted to result from an extraterrestrial impact. These proxies were found in a 27-m-long core as part of an interdisciplinary effort to extract a paleoclimate record back through the previous interglacial. Our attention focused early on an anomalous, 10-cm-thick, carbon-rich layer at a depth of 2.8 m that dates to 12.9 ka and coincides with a suite of anomalous coeval environmental and biotic changes independently recognized in other...

Hour-long hailstorm may have caused 1,000-year freeze, say scientists An hour-long hailstorm from space may have changed the climate of the Earth in 11,000 BC, leading to a freeze lasting more than 1,000 years, scientists say. Published: 8:00AM BST 02 Apr 2010 An hour-long hailstorm from space may have changed the climate of the Earth in 11,000 BC, leading to a freeze lasting more than 1,000 years, scientists say. A comet may well have caused the earth to freeze for over 1,000 years Photo: GETTY The catastrophe, caused by a disintegrating comet, wiped out large numbers of animal species and...

Nanodiamonds found across North America suggest that major climate change could have been cosmically instigatedRoughly 12,900 years ago, massive global cooling kicked in abruptly, along with the end of the line for some 35 different mammal species, including the mammoth, as well as the so-called Clovis culture of prehistoric North Americans. Various theories have been proposed for the die-off, ranging from abrupt climate change to overhunting once humans were let loose on the wilds of North America. But now nanodiamonds found in the sediments from this time period point to an alternative: a massive explosion or explosions by a fragmentary...