ScienceDaily: Ice Age News

Reading rock to understand how climate change unfolds

Sat, 18 May 2013 15:32:32 EDT

Geologists reads rock, looking for the natural rules that govern the Earth’s climate in the absence of human activity. New work is challenging many assumptions about the ways drastic climate change unfolds – and what to expect next.

Topography of Eastern Seaboard muddles ancient sea level changes

Thu, 16 May 2013 18:20:20 EDT

The distortion of the ancient shoreline and flooding surface of the US Atlantic Coastal Plain are the direct result of fluctuations in topography in the region and could have implications on understanding long-term climate change, according to a new study.

World's biggest ice sheets likely more stable than previously believed

Thu, 16 May 2013 14:25:25 EDT

A new study suggests that the previous connections scientists made between ancient shoreline height and ice volumes are erroneous and that perhaps our ice sheets were more stable in the past than we originally thought. The study found that the Earth's hot mantle pushed up segments of ancient shorelines over millions of years, making them appear higher now than they originally were millions of years ago.

World's melting glaciers making large contribution to sea rise

Thu, 16 May 2013 14:25:25 EDT

While 99 percent of Earth's land ice is locked up in the Greenland and Antarctic ice sheets, the remaining ice in the world's glaciers contributed just as much to sea rise as the two ice sheets combined from 2003 to 2009, says a new study.

Billion-year-old water could hold clues to life on Earth and Mars

Wed, 15 May 2013 13:15:15 EDT

Scientists have discovered ancient pockets of water, which have been isolated deep underground for billions of years and contain abundant chemicals known to support life. This water could be some of the oldest on the planet and may even contain life. Not just that, but the similarity between the rocks that trapped it and those on Mars raises the hope that comparable life-sustaining water could lie buried beneath the Red Planet's surface.

Fall warming on Antarctic Peninsula driven by tropically forced circulation

Wed, 15 May 2013 13:14:14 EDT

New research shows that, in recent decades, fall is the only period of extensive warming over the entire Antarctic Peninsula, and it is mostly from atmospheric circulation patterns originating in the tropics.

Warming in central China greater than most climate models indicated

Wed, 15 May 2013 09:49:49 EDT

New data from Central China reveal that temperatures have risen 10 to 14 degrees Fahrenheit over the last 20,000 years in this region, an increase two to four times greater than what many scientists previously thought.

Scientists find extensive glacial retreat in Mount Everest region

Mon, 13 May 2013 17:48:48 EDT

Researchers taking a new look at the snow and ice covering Mount Everest and the national park that surrounds it are finding abundant evidence that the world's tallest peak is shedding its frozen cloak. The scientists have also been studying temperature and precipitation trends in the area and found that the Everest region has been warming while snowfall has been declining since the early 1990s.

Carbon dioxide at NOAA's Mauna Loa Observatory reaches new milestone: Tops 400 parts per million

Fri, 10 May 2013 18:06:06 EDT

On May 9, the daily mean concentration of carbon dioxide in the atmosphere of Mauna Loa, Hawaii, surpassed 400 parts per million (ppm) for the first time since measurements began in 1958. Independent measurements made by both NOAA and the Scripps Institution of Oceanography have been approaching this level during the past week. It marks an important milestone because Mauna Loa, as the oldest continuous carbon dioxide measurement station in the world, is the primary global benchmark site for monitoring the increase of this potent heat-trapping gas.

Dust in the clouds: Cirrus clouds form around mineral dust and metallic particles

Thu, 09 May 2013 14:21:21 EDT

Cirrus clouds influence global climate, cooling the planet by reflecting incoming solar radiation and warming it by trapping outgoing heat. Understanding the mechanisms by which these clouds form may help scientists better predict future climate patterns. Scientists have now identified the major seeds on which cirrus clouds form.

Ice-free Arctic may be in our future, international researchers say

Thu, 09 May 2013 14:20:20 EDT

Analyses of the longest continental sediment core ever collected in the Arctic provide "absolutely new knowledge" of Arctic climate from 2.2 to 3.6 million years ago. The research has major implications for understanding how the Arctic transitioned from a forested landscape without ice sheets to the ice- and snow-covered land we know today.

Dietary flexibility may have helped some large predators survive after last ice age

Wed, 08 May 2013 15:14:14 EDT

During the late Pleistocene, a diverse assemblage of large-bodied mammals inhabited the "mammoth steppe" of northern Eurasia and Beringia. Of the large predators -- wolves, bears, and big cats -- only the wolves and bears were able to maintain their ranges well after the end of the last ice age. A new study suggests that dietary flexibility may have been an important factor giving wolves and bears an edge over saber-toothed cats and cave lions.

Climate change, not human activity, led to megafauna extinction

Mon, 06 May 2013 18:17:17 EDT

Most species of gigantic animals that once roamed Australia had disappeared by the time people arrived, a major review of the available evidence has concluded. The research challenges the claim that humans were primarily responsible for the demise of the megafauna in a proposed "extinction window" between 40,000 and 50,000 years ago, and points the finger instead at climate change.

The Black Sea is a goldmine of ancient genetic data

Mon, 06 May 2013 18:17:17 EDT

When one marine paleoecologist was mining through vast amounts of genetic data from the Black Sea sediment record, he was amazed about the variety of past plankton species that left behind their genetic makeup (i.e., the plankton paleome).

As climate changes, boreal forests to shift north and relinquish more carbon than expected

Sun, 05 May 2013 14:59:59 EDT

New research maps how Earth's myriad climates -- and the ecosystems that depend on them -- could move from one area to another as global temperatures rise. The approach foresees big changes for one of the planet's great carbon sponges. Boreal forests will likely shift north at a steady clip this century. Along the way, the vegetation will relinquish more trapped carbon than most current climate models predict.

Canada's distinctive tuya volcanoes reveal glacial, palaeo-climate secrets

Tue, 30 Apr 2013 13:14:14 EDT

Deposits left by the eruption of a subglacial volcano, or tuya, 1.8 million years ago could hold the secret to more accurate palaeo-glacial and climate models, according to new research. The detailed mapping and sampling of the partially eroded Kima' Kho tuya in northern British Columbia, Canada, shows that the ancient regional ice sheet through which the volcano erupted was twice as thick as previously estimated.

Climate change will raise the sea level in the Gulf of Finland

Mon, 29 Apr 2013 09:49:49 EDT

The Finnish Meteorological Institute has updated its estimates concerning the impact of rising sea levels on the Finnish coast. Post-glacial rebound and changes in the Earth’s gravity field protect the Finnish coast against rising sea levels, especially in the Gulf of Bothnia. In the Gulf of Finland, the sea level is starting to rise.

Scientists investigate release of bromine in polar regions

Fri, 26 Apr 2013 11:48:48 EDT

Researchers have employed a novel measurement device for new studies in Alaska.

Ice tubes in polar seas -- 'brinicles' or 'sea stalactites' -- provide clues to origin of life

Wed, 24 Apr 2013 11:23:23 EDT

Life on Earth may have originated not in warm tropical seas, but with weird tubes of ice -- sometimes called "sea stalactites" -- that grow downward into cold seawater near the Earth's poles, scientists are reporting.

Sunlit snow triggers atmospheric cleaning, ozone depletion in the Arctic

Wed, 24 Apr 2013 11:23:23 EDT

Researchers have discovered that sunlit snow is the major source of atmospheric bromine in the Arctic, the key to unique chemical reactions that purge pollutants and destroy ozone.

Iron in primeval seas rusted by bacteria

Tue, 23 Apr 2013 11:07:07 EDT

Researchers have been able to show for the first time how microorganisms contributed to the formation of the world's biggest iron ore deposits. The biggest known deposits -- in South Africa and Australia -- are geological formations billions of years old. They are mainly composed of iron oxides -- minerals we know from the rusting process. These iron ores not only make up most of the world demand for iron -- the formations also help us to better understand the evolution of the atmosphere and climate, and provide important information on the activity of microorganisms in the early history of life on Earth.

Geochemical method finds links between terrestrial climate and atmospheric carbon dioxide

Mon, 22 Apr 2013 15:49:49 EDT

Scientists used a new chemical technique to measure the change in terrestrial temperature associated with a major shift in global atmospheric CO2 concentrations nearly 34 million years ago. Their results provide further evidence that the concentration of atmospheric carbon dioxide and Earth's surface temperature are inextricably linked.

Earth's current warmth not seen in the last 1,400 years or more, says study

Mon, 22 Apr 2013 10:13:13 EDT

Fueled by industrial greenhouse gas emissions, Earth's climate warmed more between 1971 and 2000 than during any other three-decade interval in the last 1,400 years, according to new regional temperature reconstructions covering all seven continents.

First 2,000-year-long temperature reconstructions for individual continents

Sun, 21 Apr 2013 15:24:24 EDT

Past climate change varied remarkably between regions. This is demonstrated in a new study coordinated by the international Past Global Changes (PAGES) project, which reconstructed temperature over the past 1,000 to 2,000 years.

Remote-sensing study quantifies permafrost degradation in Arctic Alaskan wetlands

Thu, 18 Apr 2013 15:44:44 EDT

Geoscientists has achieved unprecedented detail in quantifying subtle, long-period changes in the water levels of shallow lakes and ponds in hard-to-reach Arctic wetlands.

Sea-ice ecosystem possibly triggered evolution of baleen whales and penguins

Thu, 18 Apr 2013 14:23:23 EDT

The origin of the unique plankton ecosystem of the circum-Antarctic Southern Ocean can be traced back to the emergence of the Antarctic ice sheets approximately 33.6 million years ago. This discovery shows that the development of the sea-ice ecosystem possibly triggered further adaptation and evolution of larger organisms such as baleen whales and penguins.

NASA and JAXA's GPM mission takes rain measurements global

Mon, 15 Apr 2013 12:40:40 EDT

As anyone who has ever been caught in a sudden and unexpected downpour knows, gaps still exist in our knowledge about the behavior and movement of precipitation, clouds and storms. An upcoming satellite mission from NASA and the Japan Aerospace Exploration Agency (JAXA) aims to fill in those gaps both in coverage and in scientists' understanding of precipitation.

New insight into accelerating summer ice melt on the Antarctic Peninsula

Sun, 14 Apr 2013 19:34:34 EDT

A new 1,000-year Antarctic Peninsula climate reconstruction shows that summer ice melting has intensified almost 10-fold, and mostly since the mid-20th century. Summer ice melt affects the stability of Antarctic ice shelves and glaciers.

Recent Antarctic climate, glacier changes at the 'upper bound' of normal

Sun, 14 Apr 2013 19:31:31 EDT

In the last few decades, glaciers at the edge of the icy continent of Antarctica have been thinning, and research has shown the rate of thinning has accelerated and contributed significantly to sea level rise. New ice core research suggests that, while the changes are dramatic, they cannot be attributed with confidence to human-caused global warming.

Cutting specific pollutants would slow sea level rise, research indicates

Sun, 14 Apr 2013 19:31:31 EDT

With coastal areas bracing for rising sea levels, new research indicates that cutting emissions of certain pollutants can greatly slow down sea level rise. Reductions in the four pollutants that cycle comparatively quickly through the atmosphere could forestall the rate of sea level rise by roughly 25 to 50 percent.

Arctic nearly free of summer sea ice during first half of 21st century, experts predict

Fri, 12 Apr 2013 14:28:28 EDT

For scientists studying summer sea ice in the Arctic, it's not a question of "if" there will be nearly ice-free summers, but "when." And two scientists say that "when" is sooner than many thought -- before 2050 and possibly within the next decade or two.

Warmest summers in last two decades in northern latitudes were unprecedented in six centuries

Thu, 11 Apr 2013 19:48:48 EDT

Through developing a statistical model of Arctic temperature and how it relates to instrumental and proxy records derived from trees, ice cores, and lake sediments, scientists have shown that the warmest summers in the last two decades are unprecedented in the previous six centuries.

Trouble in penguin paradise? Research analyzes Antarctic ice flow

Tue, 09 Apr 2013 11:16:16 EDT

A student researcher has discovered that a good way to monitor the environmental health of Antarctica is to go with the flow -- the ice flow, that is. It's an important parameter to track because as Antarctica's health goes, so goes the world's.

New chart shows the entire topography of the Antarctic seafloor in detail for the first time

Tue, 09 Apr 2013 11:16:16 EDT

Reliable information on the depth and floor structure of the Southern Ocean has so far been available for only few coastal regions of the Antarctic. Scientists have for the first time succeeded in creating a digital map of the entire Antarctic seafloor.

Rapid climate change and the role of the Southern Ocean

Mon, 08 Apr 2013 13:37:37 EDT

Scientists have discovered new clues about past rapid climate change. The research concludes that oceanographic reorganizations and biological processes are linked to the supply of airborne dust in the Southern Ocean and this connection played a key role in past rapid fluctuations of atmospheric carbon dioxide levels, an important component in the climate system.

Dramatic retreat of the Andean glaciers over the last 30 years

Mon, 08 Apr 2013 12:28:28 EDT

The glaciers in the tropical Andes shrunk between 30 and 50% in 30 years, which represents the highest rate observed over the last three centuries. Scientists have recently published a summary which chronicles the history of these glaciers since their maximum extension, reached between 1650 and 1730 of our era, in the middle of the Little Ice Age. The faster melting is due to the rapid climate change which has occurred in the tropics since the 1950s, and in particular since the end of the 1970s, leading to an average temperature rise of 0.7°C in this part of the Andes. At the current pace of their retreat, small glaciers could disappear within the next 10 to 15 years, affecting water supply for the populations.

New measurement of crocodilian nerves could help scientists understand ancient animals

Thu, 04 Apr 2013 15:26:26 EDT

A new study has measured the nerves responsible for the super-sensitive skin on a crocodile's face, which will help biologists understand how today's animals, as well as dinosaurs and crocodiles that lived millions of years ago, interact with the environment around them.

Discovery of 1,800-year-old 'Rosetta Stone' for tropical ice cores

Thu, 04 Apr 2013 14:24:24 EDT

Scientists report a set of ice cores from Quelccaya Ice Cap in Peru which can serve as a "Rosetta Stone" for studying other ice cores from around the world.

Dwarf whale survived well into Ice Age

Thu, 04 Apr 2013 12:21:21 EDT

Research detailing the fossil of a dwarf baleen whale from Northern California reveals that it avoided extinction far longer than previously thought.

Climate change winners: Adélie penguin population expands as ice fields recede

Thu, 04 Apr 2013 09:28:28 EDT

Adelie penguins may actually benefit from warmer global temperatures, the opposite of other polar species, according to a breakthrough study. The study provides key information affirming hypothetical projections about the continuing impact of environmental change.

2013 wintertime Arctic sea ice maximum fifth lowest on record

Wed, 03 Apr 2013 14:14:14 EDT

During the cold and dark of Arctic winter, sea ice refreezes and achieves its maximum extent, usually in late Feb. or early Mar. According to a NASA analysis, this year the annual maximum extent was reached on Feb. 28 and it was the fifth lowest sea ice winter extent in the past 35 years.

'A better path' toward projecting, planning for rising seas on a warmer Earth

Wed, 03 Apr 2013 14:14:14 EDT

More useful projections of sea level are possible despite substantial uncertainty about the future behavior of massive ice sheets. In two recent articles, researchers present an approach that provides a consistent means to integrate the potential contribution of continental ice sheets such as Greenland and Antarctica into sea-level rise projections.

Ancient pool of warm water questions current climate models

Wed, 03 Apr 2013 13:13:13 EDT

A huge pool of warm water that stretched out from Indonesia over to Africa and South America four million years ago suggests climate models might be too conservative in forecasting tropical changes. Present in the Pliocene era, this giant mass of water would have dramatically altered rainfall in the tropics, possibly even removing the monsoon. Its decay and the consequential drying of East Africa may have been a factor in Hominid evolution. The missing data for this phenomenon could have significant implications when predicting the future climate.

Ancient climate questions could improve today's climate predictions

Wed, 03 Apr 2013 13:13:13 EDT

Climate models for the early Pliocene might be missing key processes. If researchers can uncover these missing processes, they can apply them to models of modern climate and improve future climate predictions.

Thin clouds drove Greenland's record-breaking 2012 ice melt

Wed, 03 Apr 2013 13:13:13 EDT

If the sheet of ice covering Greenland were to melt in its entirety tomorrow, global sea levels would rise by 24 feet. Three million cubic kilometers of ice won't wash into the ocean overnight, but researchers have been tracking increasing melt rates since at least 1979. Last summer, however, the melt was so large that similar events show up in ice core records only once every 150 years or so over the last four millennia.

Breeding birds vulnerable to climate change in arctic alaska: A story of winners and losers

Wed, 03 Apr 2013 09:25:25 EDT

A new report looked at the vulnerability of 54 breeding bird species to climate change impacts occurring by the year 2050 in Arctic Alaska. The assessment found that two species, the gyrfalcon and common eider are likely to be “highly” vulnerable, while seven other species would be “moderately” vulnerable to anticipated impacts. Five species are likely to increase in number and benefit from a warming climate.

Research examines ancient Puebloans and the myth of maize

Tue, 02 Apr 2013 15:24:24 EDT

New research shows that perhaps the ancient Puebloans weren't as into the maize craze as once thought. Nikki Berkebile has been studying the subsistence habits of Puebloans, or Anasazi, who lived on the southern rim of the Grand Canyon in the late 11th century. Traditional ethnographic literature indicates these ancient American Indians were heavily dependent on maize as a food source, but Berkebile isn't so sure about that.

Cold cities less sustainable than warm cities, research suggests

Thu, 28 Mar 2013 07:57:57 EDT

Living in colder climates in the US is more energy demanding than living in warmer climates. Scientists have calculated that climate control in the coldest large metropolitan area in the country – Minneapolis – is about three-and-a-half times more energy demanding than in the warmest large metropolitan area – Miami.

Summer melt season getting longer on Antarctic Peninsula

Wed, 27 Mar 2013 13:37:37 EDT

New research from the Antarctic Peninsula shows that the summer melt season has been getting longer over the last 60 years. Increased summer melting has been linked to the rapid break-up of ice shelves in the area and rising sea level.

Climate models are not good enough, researcher argues

Mon, 25 Mar 2013 09:35:35 EDT

Only a few climate models were able to reproduce the observed changes in extreme precipitation in China over the last 50 years.

Global nitrogen availability consistent for past 500 years linked to carbon levels

Thu, 21 Mar 2013 10:51:51 EDT

Despite humans increasing nitrogen production through industrialization, nitrogen availability in many ecosystems has remained steady for the past 500 years, a new study finds.

Roman mausoleum tested for ancient earthquake damage

Wed, 20 Mar 2013 15:52:52 EDT

A Roman mausoleum was knocked off-kilter, and the likely cause was an earthquake, according to a new detailed model.

For polar bears, it's survival of the fattest

Tue, 19 Mar 2013 20:20:20 EDT

One of the most southerly populations of polar bears in the world – and the best studied – is struggling to cope with climate-induced changes to sea ice, new research reveals. Based on over 10 years' data the study sheds new light on how sea ice conditions drive polar bears' annual migration on and off the ice.

Oxygen-poor 'boring' ocean challenged evolution of early life

Mon, 18 Mar 2013 15:15:15 EDT

Biogeochemists have filled in a billion-year gap in our understanding of conditions in the early ocean during a critical time in life's history on Earth. During the period 1.8 to 0.8 billion years ago, oxygen likely remained low in the atmosphere and ocean, with marine life dominated by bacteria. The ocean was oxygen-free and iron-rich in the deepest waters and hydrogen sulfide-containing over limited regions on the ocean margins.

Ten times more hurricane surges in future, new research predicts

Mon, 18 Mar 2013 15:15:15 EDT

How much worse will the frequency of extreme storm surges get as temperatures rise in the future? How many extreme storm surges like that from Hurricane Katrina, which hit the U.S. coast in 2005, will there be as a result of global warming? New research shows that there will be a tenfold increase in frequency if the climate becomes two degrees Celsius warmer.

Significant contribution of Greenland's peripheral glaciers to sea-level rise

Mon, 18 Mar 2013 10:49:49 EDT

Glaciers at the edge of Greenland which are not connected to its huge ice sheet, or can be clearly separated from it, are contributing to sea-level rise much more than previously thought. Scientists have found that, though these peripheral glaciers make up just 5 to 7 percent of total ice coverage on the land mass, they account for up to 20 percent of the rise in sea level created by the region's melting.

Polar bears' family secrets revealed with DNA sequencing

Thu, 14 Mar 2013 18:01:01 EDT

Brown bears on an Alaskan archipelago are the descendants of an ancient polar bear population rather than being the ancestors of modern polar bears, new research shows.

DNA study clarifies how polar bears and brown bears are related

Thu, 14 Mar 2013 17:56:56 EDT

A new genetic study of polar bears and brown bears upends prevailing ideas about the evolutionary history of the two species.

Dinosaur-era climate change study suggests reasons for turtle disappearance

Thu, 14 Mar 2013 14:43:43 EDT

Dramatic climate change was previously proposed to be responsible for the disappearance of turtles 71-million-years ago, because they were considered to be "climate-sensitive" animals. Results of this research, however, show that the disappearance of turtles came before the climate cooled and instead closely corresponds to habitat disturbances, which was the disappearance of wetlands.

Canadian Arctic glacier melt accelerating, irreversible, projections suggest

Tue, 12 Mar 2013 13:49:49 EDT

Ongoing glacier loss in the Canadian high Arctic is accelerating and probably irreversible, new model projections suggest. The Canadian high Arctic is home to the largest clustering of glacier ice outside of Greenland and Antarctica -- 146,000 square kilometers (about 60,000 square miles) of glacier ice spread across 36,000 islands.