Trees Face Rising Drought Stress and Mortality as Climate Warms
LOS ALAMOS, N.M. — Combine the tree-ring growth record with historical information, climate records, and computer-model projections of future climate trends, and you get a grim picture for the future of trees in the southwestern United States. That’s the word from a team of scientists from Los Alamos National Laboratory, the U.S. Geological Survey, University of Arizona, and other partner organizations.
The research, published in Nature Climate Change this week, concluded that if the Southwest is warmer and drier in the near future, widespread tree mortality likely will cause substantial changes in forest and species distributions. (more…)
Michelle Bayefsky hopes that London’s future will be filled with elm trees.
The Yale junior spent part of her summer in that city helping to ensure that will be the case.
An International Bulldogs Internship allowed Bayefsky the opportunity to work for an environmental charity called The Conservation Foundation, which among other initiatives is engaged in a project to re-establish elm tree populations in the United Kingdom (U.K.). For Bayefsky, the experience was not only an introduction to environmental work, but also confirmed that small actions can sometimes have a big impact. (more…)
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…)
A new study has found that climate-prediction models are good at predicting long-term climate patterns on a global scale but lose their edge when applied to time frames shorter than three decades and on sub-continental scales.
Climate-prediction models show skills in forecasting climate trends over time spans of greater than 30 years and at the geographical scale of continents, but they deteriorate when applied to shorter time frames and smaller geographical regions, a new study has found.(more…)
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…)
A NASA-sponsored expedition is set to sail to the North Atlantic’s saltiest spot to get a detailed, 3-D picture of how salt content fluctuates in the ocean’s upper layers and how these variations are related to shifts in rainfall patterns around the planet.
The research voyage is part of a multi-year mission, dubbed the Salinity Processes in the Upper Ocean Regional Study (SPURS), which will deploy multiple instruments in different regions of the ocean. The new data also will help calibrate the salinity measurements NASA’s Aquarius instrument has been collecting from space since August 2011. (more…)
Blanket bogs, which provide vital habitats for a unique range of plants, birds, small mammals, reptiles and amphibians, are at risk of declining as a result of climate change.
Research by the Universities of Exeter and Bristol in the UK and Macquarie University in Australia, published in the journal Nature Climate Change, shows for the first time how rising temperatures will threaten these sensitive ecosystems.
The study highlights the urgency of developing a plan to protect these important habitats.
Found in wet, coastal areas of high latitude regions, blanket bogs cover around 700,000 hectares of land in the UK, much of it designated as a Site of Special Scientific Interest (SSSI). Blanket bogs are found in the north and west of the UK, extending from Devon in the south to Shetland in the north, and it has been estimated that 10 to15 per cent of the world’s blanket bog occurs in Britain. As well as being crucial in supporting wildlife, blanket bogs also capture and store large amounts of carbon, helping to mitigate against climate change, and reduce the risk of flooding, by slowing down water flow. With some blanket peat being over 9,000 years old, they also hold historically-significant archaeological material. (more…)
Researchers at the UH Manoa School of Ocean and Earth Science and Technology (SOEST) made a discovery that challenges a major theory in the field of coral reef ecology.
The general assumption has been that the more flexible corals are, regarding which species of single-celled algae (Symbiodinium) they host in coral tissues, the greater ability corals will have to survive environmental stress. In their paper published August 29, 2012, however, scientists at the Hawaii Institute of Marine Biology (HIMB) at SOEST and colleagues documented that the more flexible corals are, the more sensitive to environment disturbances they are. (more…)
