AGU期刊一周Research Spotlight (Mar 24~Mar 30, 2016)

发布时间:2016-3-31 11:03:37 点击次数:1004
 

I. Atmospheric Sciences

1.High-Resolution Climate Modeling for Regional Adaptation

High-Resolution Climate Modeling in the Northern Great Plains; Boulder, Colorado, 24–25 September 2015

 

II. Geology & Geophysics

1.Investigations of Shallow Slow Slip Offshore of New Zealand

Recent and upcoming studies of the Hikurangi margin east of New Zealand shed light on previously undetectable tectonic movements.

2.Eos Wins Gold Medal for Most Improved Publication

The revitalized magazine and website have been honored three times in 14 months.

 

III. Biogeosciences

1. Algae Blooms and Gas Wells Drive Lake Erie Methane Emissions 

In one of the first studies to investigate large lakes as methane sources, researchers found that Lake Erie is releasing more of the potent greenhouse gas than expected.

 

IV. Ocean Sciences

1.Frontiers in Geosystems: Solving the Puzzles

Putting some publishing action into deep Earth-surface interactions.

2.Navy Ship Mysteriously Lost in 1921 Found via Science, Sleuthing

Scientists painstakingly compared a shipwreck spotted in 2009 to a 1904 schematic of a long-lost tugboat. A naval gun on the wreck proved to be the "smoking gun" identifying the vanished ship.

3.Joint Polar Satellite System Algorithm Team Reviews Past, Future

Center for Satellite Applications and Research Joint Polar Satellite System Annual Science Team Meeting; College Park, Maryland, 24–28 August 2015

 

V. Space Science & Space Physics

1.Radiation Belt Processes in a Declining Solar Cycle

The Van Allen Probes began an extended mission in November to advance understanding of Earth's radiation belts.

 

. Climate Change

1.New Interest in Reservoir Evaporation in Western United States

Reservoir Evaporation Workshop; Boulder, Colorado, 22–23 October 2015  

2.Current Carbon Emissions Unprecedented in 66 Million Years

An ancient carbon dioxide release associated with a much hotter Earth than today took place at only a tenth the pace of our present atmospheric carbon buildup, a new study confirms.

3.Upcoming Arctic Summit to Include Focus on Climate Change

U.S. initiatives aim to protect the marine environment and address climate change in the Arctic, U.S. ambassador says.

4.White House Summit Focuses on Solutions to Water Challenges

Announced initiatives included funding for water research, development, and infrastructure projects; the launch of a new National Water Model; and the release of a drought resilience action plan.

5.Anticipating Cascading Effects from Climate Extremes

Preparing for High Consequence, Low Probability Events: Heat, Water & Energy in the Southwest; Tucson, Arizona, 28–29 September 2015

 

. Hydrology, Cryosphere& Earth Surface

1.Hitting the Slopes

Researchers investigate whether rain droplets alone can cause enough erosion to impact the shapes of hills.

2.Temperature-Sensing Overalls Offer Scientific Promise

In a proof-of-concept experiment, researchers test out how well a pair of fisherman's waders can sense changes in water temperature.

 

Ⅷ:Geophysical Research Letters

1.Tropical cloud buoyancy is the same in a world with or without ice

When convective clouds grow above the melting line, where temperatures fall below zero degrees Celsius, condensed water begins to freeze and water vapor is deposited. These processes release the latent heat of fusion, which warms cloud air, and many previous studies have suggested that this heating from fusion increases cloud buoyancy in the upper troposphere. Here, we use numerical simulations of radiative-convective equilibrium with and without ice processes to argue that tropical cloud buoyancy is not systematically higher in a world with fusion than in a world without it. This insensitivity results from the fact that the environmental temperature profile encountered by developing tropical clouds is itself determined by convection. We also offer a simple explanation for the large reservoir of convective available potential energy (CAPE) in the tropical upper troposphere that does not invoke ice.

2. The stratospheric pathway for Arctic impacts on mid-latitude climate

Recent evidence from both observations and model simulations suggests that an Arctic sea-ice reduction tends to cause a negative Arctic Oscillation (AO) phase with severe winter weather in the Northern Hemisphere, which is often preceded by weakening of the stratospheric polar vortex. Although this evidence hints at a stratospheric involvement in the Arctic–mid-latitude climate linkage, the exact role of the stratosphere remains elusive. Here we show that tropospheric AO response to the Arctic sea-ice reduction largely disappears when suppressing the stratospheric wave–mean flow interactions in numerical experiments. The results confirm a crucial role of the stratosphere in the sea-ice impacts on the mid-latitudes by coupling between the stratospheric polar vortex and planetary-scale waves. Those results and consistency with observation-based evidence suggest that a recent Arctic sea-ice loss is linked to mid-latitudes extreme weather events associated with the negative AO phase.

3.The long-term trend in the diurnal temperature range over Asia and its natural and anthropogenic causes

Understanding the causes of long-term temperature trends is at the core of climate change studies. Any observed trend can result from natural variability or anthropogenic influences, or both. In the present study, we evaluated the performance of 18 climate models from the Coupled Model Intercomparison Project Phase 5 on simulating the Asian diurnal temperature range (DTR), and explored the potential causes of the long-term trend in the DTR by examining the response of the DTR to natural forcing (volcanic aerosols and solar variability) and anthropogenic forcing (anthropogenic greenhouse gases (GHG) and aerosols) in the historical period of 1961-2005. For the climatology, the multi-model ensemble mean reproduced the geographical distribution and amplitude of the DTR over eastern China and India, but underestimated the magnitudes of the DTR over the Tibetan Plateau and the high-latitude regions of the Asian continent. These negative biases in the DTR over frigid zones existed in most models. Seasonal biases in the DTR pattern from models were similar to the bias in the annual mean DTR pattern. Based on three selected state-of-the-art models, the observed decreasing trend in the DTR over Asia was reasonably reproduced in the all-forcing run. A comparison of separate forcing experiments revealed that anthropogenic forcing plays the dominant role in the declining trend in the DTR. Observations and model simulations showed that GHG forcing is mainly responsible for the negative trends in the DTR over Asia, but that anthropogenic aerosol forcing was also behind the decreasing trend in the DTR over China, and especially over eastern China.

4. The differing biogeochemical and microbial signatures of glaciers and rock glaciers

Glaciers and rock glaciers supply water and bioavailable nutrients to headwater mountain lakes and streams across all regions of the American West. Here we present a comparative study of the metal, nutrient, and microbial characteristics of glacial and rock glacial influence on headwater ecosystems in three mountain ranges of the contiguous U.S.: the Cascade Mountains, Rocky Mountains, and Sierra Nevada. Several meltwater characteristics (water temperature, conductivity, pH, metals, nutrients, complexity of dissolved organic matter (DOM), and bacterial richness and diversity) differed significantly between glacier and rock glacier meltwaters, while other characteristics (Ca2+, Fe3+, SiO2 concentrations, reactive nitrogen, and microbial processing of DOM) showed distinct trends between mountain ranges regardless of meltwater source. Some characteristics were affected both by glacier type and mountain range (e.g., temperature, ammonium (NH4+) and nitrate (NO3) concentrations, and bacterial diversity). Due to the ubiquity of rock glaciers and the accelerating loss of the low-latitude glaciers, our results point to the important and changing influence that these frozen features place on headwater ecosystems.

 

Ⅸ:The Landslide Blog

1. Remarkable new footage of the mudflow from the Samarco tailings dam failure in Brazil

An amazing new video has appeared on Youtube showing the mudflow that was released by the Samarco tailings dam failure in Brazil on 15th November 2015.  I covered this event at the time, and investigations continue into the cause and blame.  This video is accompanied by some text in Portuguese.  Google Translate, with some edits by me, renders this as follows:

In an unprecedented video posted by one of the witnesses of the tragedy on a social network can be seen the strength of brown mudflow that came down from the mountains, reaching and destroying communities and all that was ahead. The desperation is of the three people who were close to Bento Rodrigues, Mariana district of Minas Gerais Central Region, which wasdevastated by mud tailings  from the Fundão dam, on November 5, 2015

 

Ⅹ:Earth and Space Sciense

1.New satellite could provide better data for hurricane prediction

Researchers have found a better way to use satellite data in hurricane prediction models, which could revolutionize future hurricane predictions. Pictured is satellite imagery of Hurricane Karl, which was the focus of a new proof-of-concept study.