World Bulletin / News Desk
A big expansion of Antarctica's ice almost a million years ago may help scientists predict modern climate change, a study showed.
The report, examining the Earth's orbit around the sun in a 100,000-year cycle of cold and warmth, showed that ice sheets took thousands of years to grow at the start of Ice Ages and surprisingly lagged a quicker cooling of the oceans.
That delay, and the discovery of a large buildup of ice into the Southern Ocean around Antarctica 900,000 years ago, is a step towards understanding the climate system and its link to changes in the planet's orbit, they said.
That in turn could help predict current global warming.
"When we think of future climate change we think about everything happening together," said Harry Elderfield, a professor at Cambridge University and lead author of the study in Friday's edition of the journal Science.
"We might think that it's warmer so sea level would change at the same time" as ice melts on the land and adds to the oceans. "What we are seeing is that things are changing, not really in concert."
"The deep sea cooled to nearly freezing temperatures early in any given glacial cycle, whereas globalice volume typically increased gradually," Peter Clark of Oregon State University wrote in a separate commentary in Science on the findings.
Elderfield's team found records of both sea temperatures and ice volumes by studying the chemical makeup of tiny marine fossils in the seabed off New Zealand.
The last Ice Age was at a maximum about 20,000 years ago and the Earth is into a natural warmer period in a cycle expected to last about 100,000 years.
But manmade global warming is now the main cause of a rise in temperatures in the past half-century, according to the U.N. panel of climate scientists which projects ever more floods, droughts and rising sea levels.
Until now, most experts have believed that Ice Ages were seen mainly in changes in the volume of icearound the North Pole -- giant ice sheets blanketed much of the Northern Hemisphere at the height of the last Ice Age.
"The assumption had been that the big cycles in the Ice Ages occurred with ice volume in the Arctic. We are finding that is not the case. We are finding that Antarctica is changing," Elderfield said.
And the growth of Antarctic ice 900,000 years ago apparently initiated a previously unexplained shift in the cycle of Ice Ages and warmer periods to the current 100,000 years from 41,000 years, they said. Both periods are linked to Earth's orbit.
Scientists previously have been unable to separate information in fossils about the volume of ice on the planet from information about changing temperatures, Elderfield said.
They found that the amount of magnesium indicated changes in temperatures in the fossils and the exact makeup of oxygen indicated the amount of ice.
Product available for pre-order in nine countries but devices won’t ship for weeks.
Nobel Prize-winning scientists' discovery can be manufactured cheaper thanks to Nanografi process.
Most industry experts expect the first product of 5G technology in the run-up to the Tokyo Olympics in 2020.
The slowdown in the rate of rising temperatures, from faster gains in the 1980s and 1990s, has puzzled scientists because heat-trapping greenhouse gas emissions
The discovery challenges currently held theories that black holes and their host galaxies grew in relative lockstep over the eons.
Australian researchers are developing the new way to have a final product for Boeing Co, Airbus Group NV, very quickly than now. 3D printing can cut production times for components from three months to just six days.
Bogachev is charged in the United States with running a computer attack network called GameOver Zeus that allegedly stole more than $100 million from online bank accounts.
The account started sharing videos and photos of the militant group a few days ago
U.S., UK spies hacked SIM card maker Gemalto's system, Intercept says, giving spies ability to monitor calls on billions of phones
The next time an earthquake hits the Pacific Northwest, a handful of computers in offices across the region will have access to a software that will send out an alarm, alerting people before the earthquake strikes.
Researchers in Britain have discovered that limpet teeth exhibit a strength that is potentially higher than spider silk.
Epigenetic differences are one reason identical twins, who have identical DNA, do not always develop the same genetic diseases, including cancer.
Kaspersky said it found personal computers in 30 countries infected with one or more of the spying programs, with the most infections seen in Iran, followed by Russia, Pakistan, Afghanistan, China, Mali, Syria, Yemen and Algeria.
The makers of mobile travel app "Bey2ollak" have warn on bomb scares and resulting hold-ups in Cairo and Alexandria using the hashtag #WhereIsTheBomb.
The preschool programme, aimed at children aged between three and six, is based on the Finnish National Curriculum, widely considered one of the world's best education systems.