Tag Archives: Arctic

Analysis of Greenland Ice Cores Adds to Historical Record and May Provide Glimpse into Climate’s Future

By Guest PostJanuary 30, 2013Environmentalpine research, Antarctica, Arctic, arctic sciences section, atmosphere, belgium, boulder, canada, change, China, climate, climate conditions, denmark, dorthe dahl-jensen, earth climate, eemian interglacial, eemian like, eemian period, france, future, future climate, Germany, global temperatures rise, greenland ice cores, greenland ice sheet, historical record, ice ages, ice sheet, Iceland, Japan, jim white, last interglacial period, national science foundation, neem, northern greenland, northern hemisphere, paleo climate models, sea-level rise, south korea, subsurface ice layers, Sweden, switzerland, the netherlands, united kingdom, united states, university of colorado, university of copenhagen, west antarctic

The International North Greenland Eemian Ice Drilling (NEEM) project results indicate that melting of Antarctic ice sheet may have contributed more to sea level rise than melting of the Greeland ice sheet some 100,000 years ago

A new study that provides surprising details on changes in Earth’s climate from more than 100,000 years ago indicates that the last interglacial–the period between “ice ages”–was warmer than previously thought and may be a good analog for future climate, as greenhouse gases increase in the atmosphere and global temperatures rise.

The research findings also indicate that melting of the massive West Antarctic ice sheet may have contributed more to sea-level rise at that time than melting of the Greenland ice sheet. (more…)

Climate Change Study Strengthens Link to Human Activities

By Guest PostDecember 5, 2012EnvironmentAntarctica, Arctic, atmospheric temperature, benjamin santer, berkeley lab, carbon dioxide, cfcs, chlorofluorocarbons, climate change, climate models, coolants, el niño, evidence, greenhouse gases, higgs boson, human factors, human influence, llnl, michael wehner, pacific decadal oscillation, phenomena, propellants, satellite data, simulations, southern oscillation, stratospheric temperature, tropospheric, tropospheric warming

Computer Models, Satellite Data Reveal Clearest Evidence Yet of Human Influence on Changing Temperatures

New research shows some of the clearest evidence yet of a discernible human influence on atmospheric temperature.

Published online in the Nov. 29 early edition of the Proceedings of the U.S. National Academy of Sciences, the study compared 20 of the latest climate models against 33 years of satellite data. When human factors were included in the models, they followed the pattern of temperature changes observed by satellite. When the same simulations were run without considering human influences, the results were quite different.

“We can only match the satellite record when we add in human influences on the atmosphere,” said Michael Wehner, a research scientist at Lawrence Berkeley National Laboratory (Berkeley Lab) Computational Research Division and a coauthor of the article, which involved colleagues from 16 other organizations and was led by Benjamin Santer, an atmospheric scientist at Lawrence Livermore National Laboratory (LLNL). (more…)

USGS Study Tracks Pacific Walrus, Observes Effects of Arctic Sea Ice Loss on Behavior

By Guest PostNovember 15, 2012Environment, NatureArctic, Arctic sea ice, behavioral change, chukchi sea, ecosystems, feeding grounds, female walrus, gas, geoffrey haskett, hanna shoal region, iconic arctic species, lease blocks, marcia mcnutt, marine mammals, melting, mortality, northern, oil, pacific walruses, polar bears, russian scientists, s a sonsthagen, sea ice, summer, trampling, U.S. Geological Survey, walrus population

ANCHORAGE, Alaska — Sparse summer sea ice in the Arctic over the past five years has caused behavioral changes in Pacific walruses according to research published by U.S. Geological Survey and Russian scientists. The effects on the walrus population are unknown.

“The loss of sea ice is the ‘why’ for the change in walrus behavior; the tracking data tells us the ‘where’ in terms of their new forage patterns,” said USGS Director Marcia McNutt. “What awaits to be seen is ‘how much will it matter?'” (more…)

2001-02 Drought Helped to Shift Rocky Mountain Pine Beetle Outbreak into Epidemic

By Guest PostNovember 5, 2012Environment19th century, alpine research, Arctic, beetles, boulder, british columbia, climate, colorado, continental divide, drought, dynamics, epidemic, episode, evan pugh, forest, front range, lodgepole pine, mountain, native insect, new mexico, North America, northern, pine beetle, ponderosa pine, precipitation, rocky mountains, tania schoennagel, teresa chapman, thomas veblen, university, warmer climate, western slope, wyoming

A new University of Colorado Boulder study shows for the first time that episodes of reduced precipitation in the southern Rocky Mountains, especially during the 2001-02 drought, greatly accelerated development of the mountain pine beetle epidemic.

The study, the first ever to chart the evolution of the current pine beetle epidemic in the southern Rocky Mountains, compared patterns of beetle outbreak in the two primary host species, the ponderosa pine and lodgepole pine, said CU-Boulder doctoral student Teresa Chapman. The current mountain pine beetle outbreak in the southern Rockies — which range from southern Wyoming through Colorado and into northern New Mexico –is estimated to have impacted nearly 3,000 square miles of forests, said Chapman, lead study author. (more…)

Shrinking Snow Depth on Arctic Sea Ice Threatens Ringed Seal Habitat

By Guest PostSeptember 20, 2012EnvironmentArctic, atmospheric sciences, brendan kelly, cecilia bitz, climate change, climate model, ice, important factor, paul hezel, predict, pups, sea ice, seals, shrink, snowfall pattern, thermodynamic impact, thickness, university, Washington

As sea ice in the Arctic continues to shrink during this century, more than two thirds of the area with sufficient snow cover for ringed seals to reproduce also will disappear, challenging their survival, scientists report in a new study.

The ringed seal, currently under consideration for threatened species listing, builds caves to rear its young in snow drifts on sea ice. Snow depths must be on average at least 20 centimeters, or 8 inches, to enable drifts deep enough to support the caves. (more…)

CU-led Mountain Forest Study Shows Vulnerability to Climate Change

By Guest PostSeptember 16, 2012Environmentalpine, anne kelly, Arctic, atmosphere, boulder, carbon dioxide, change, climate change, colorado, data, dry, energy, ernesto trujillo, flux towers, forest greenness, ground measurement, high resolution, michael golden, mid elevation, moisture change, mountain ecosystem, mountain range, noah molotch, precipitation, radiometer, rising temperature, roger bales, satellite image, sensitivity, sierra nevada, snowmelt, tipping point, united states, university, water vapor, western, wet, year

A new University of Colorado Boulder-led study that ties forest “greenness” in the western United States to fluctuating year-to-year snowpack indicates mid-elevation mountain ecosystems are most sensitive to rising temperatures and changes in precipitation and snowmelt.

Led by CU-Boulder researcher Ernesto Trujillo and Assistant Professor Noah Molotch, the study team used the data — including satellite images and ground measurements — to identify the threshold where mid-level forests sustained primarily by moisture change to higher-elevation forests sustained primarily by sunlight and temperature. Being able to identify this “tipping point” is important because it is in the mid-level forests — at altitudes from roughly 6,500 to 8,000 feet — where many people live and play in the West and which are associated with increasing wildfires, beetle outbreaks and increased tree mortality, said Molotch. (more…)

On The Front Lines

By Guest PostSeptember 4, 2012Environmentandreas muenchow, Arctic, blog, canada, canadian icebreaker, delaware, extent, front lines, greenland, henry larsen, ice, ice cover, ice island, ice loss, icy seas, manhattan, marine scientist, melt cycle, multi year, nares strait, nsidc, petermann fjord, petermann glacier, sea ice, ud scientist, university

UD scientist sees Arctic ice loss firsthand

The extent of sea ice in the Arctic has reached a record low, according to data released Aug. 26 by the U.S. National Snow and Ice Data Center (NSIDC).

A University of Delaware marine scientist can confirm some of that ice loss firsthand. In a short video he produced, Andreas Muenchow, aboard the Canadian icebreaker Henry Larsen, shows the ice-free sea off Petermann Fjord that he and his colleagues were sailing in — an area that for ages had been covered by floating ice shelves. (more…)

Climate Change Could Increase Levels of Avian Influenza in Wild Birds

By Guest PostAugust 31, 2012Environment, Naturea h5n1, american black duck, Arctic, avian influenza, biogeographic population, bird flu, choreographed interaction, climate change, delaware bay, domestic poultry, heat waves, horseshoe crab, human health, human infection, increase, influenza infection, level, mallards, mathematical model, melting glaciers, michigan, migratory flight, migratory paths, migratory shorebird, north american, pejman rohani, planetary woes, population ecologist, rainstorms, risk, sea levels, species, type a virus, university, victoria brown, western hemisphere, wild birds

ANN ARBOR, Mich.— Rising sea levels, melting glaciers, more intense rainstorms and more frequent heat waves are among the planetary woes that may come to mind when climate change is mentioned. Now, two University of Michigan researchers say an increased risk of avian influenza transmission in wild birds can be added to the list.

Population ecologists Pejman Rohani and Victoria Brown used a mathematical model to explore the consequences of altered interactions between an important species of migratory shorebird and horseshoe crabs at Delaware Bay as a result of climate change. (more…)