While the rest of world has warmed, Antarctica has grown chillier, scientists say. According to a new study, air temperature on the southernmost continent fell by 0.7 degree Celsius per decade between 1986 and 2000 - a cooling trend that has come with ecological consequences.
The findings may come as a surprise to climate researchers. Conventional wisdom holds that the polar regions should be the first to show the effects of global warming. And previous work has indeed detected increased temperatures in Antarctica. But those studies, Peter T. Doran of the University of Illinois and colleagues note, used data collected from the Antarctic Peninsula, which extends north toward South America. Doran and his team, in contrast, analyzed a 14-year continuous weather station record from a cold, snow-less desert known as the dry valleys region—the continent’s largest ice-free area. The results of that analysis, in combination with a 35-year continental temperature compilation, suggest that temperature readings from the more numerous Peninsula stations have misrepresented the situation. "Our approach," Doran remarks, "shows that if you remove the Peninsula from the data set and look at the spatial trend, the majority of the continent is cooling."
Furthermore, the observed cooling is seasonal, affecting summer and fall temperatures the most. Summer cooling can have an especially dramatic impact on the organisms in Antarctica’s fragile terrestrial ecosystems, where liquid water is of limited availability. In fact, the continent’s cooling trend already appears to have affected life in the dry valleys, the researchers note. Decreased productivity of the region’s lakes may well stem from a climate-induced increase in lake ice thickness, which cuts down on the amount of light that reaches the resident phytoplankton. Changes in the abundance of soil-dwelling invertebrates have occurred as well, the team reports, declining in some cases by 10 percent per year. Prolonged summer cooling, the investigators thus propose, "will diminish aquatic and soil biological assemblages throughout the valleys and possibly in other terrestrial Antarctic ecosystems."
Kate Wong | Scientific American
Hundreds of bubble streams link biology, seismology off Washington's coast
22.03.2019 | University of Washington
Atmospheric scientists reveal the effect of sea-ice loss on Arctic warming
11.03.2019 | Institute of Atmospheric Physics, Chinese Academy of Sciences
DESY and MPSD scientists create high-order harmonics from solids with controlled polarization states, taking advantage of both crystal symmetry and attosecond electronic dynamics. The newly demonstrated technique might find intriguing applications in petahertz electronics and for spectroscopic studies of novel quantum materials.
The nonlinear process of high-order harmonic generation (HHG) in gases is one of the cornerstones of attosecond science (an attosecond is a billionth of a...
Nano- and microtechnology are promising candidates not only for medical applications such as drug delivery but also for the creation of little robots or flexible integrated sensors. Scientists from the Max Planck Institute for Polymer Research (MPI-P) have created magnetic microparticles, with a newly developed method, that could pave the way for building micro-motors or guiding drugs in the human body to a target, like a tumor. The preparation of such structures as well as their remote-control can be regulated using magnetic fields and therefore can find application in an array of domains.
The magnetic properties of a material control how this material responds to the presence of a magnetic field. Iron oxide is the main component of rust but also...
Due to the special arrangement of its molecules, a new coating made of corn starch is able to repair small scratches by itself through heat: The cross-linking via ring-shaped molecules makes the material mobile, so that it compensates for the scratches and these disappear again.
Superficial micro-scratches on the car body or on other high-gloss surfaces are harmless, but annoying. Especially in the luxury segment such surfaces are...
The Potsdam Echelle Polarimetric and Spectroscopic Instrument (PEPSI) at the Large Binocular Telescope (LBT) in Arizona released its first image of the surface magnetic field of another star. In a paper in the European journal Astronomy & Astrophysics, the PEPSI team presents a Zeeman- Doppler-Image of the surface of the magnetically active star II Pegasi.
A special technique allows astronomers to resolve the surfaces of faraway stars. Those are otherwise only seen as point sources, even in the largest telescopes...
Researchers at Chalmers University of Technology and the University of Gothenburg, Sweden, have proposed a way to create a completely new source of radiation. Ultra-intense light pulses consist of the motion of a single wave and can be described as a tsunami of light. The strong wave can be used to study interactions between matter and light in a unique way. Their research is now published in the scientific journal Physical Review Letters.
"This source of radiation lets us look at reality through a new angle - it is like twisting a mirror and discovering something completely different," says...
11.03.2019 | Event News
01.03.2019 | Event News
28.02.2019 | Event News
22.03.2019 | Life Sciences
22.03.2019 | Life Sciences
22.03.2019 | Information Technology