A recent NASA-funded study has linked the 1991 eruption of the Mount Pinatubo to a strengthening of a climate pattern called the Arctic Oscillation. For two years following the volcanic eruption, the Arctic Oscillation caused winter warming over land areas in the high and middle latitudes of the Northern Hemisphere, despite a cooling effect from volcanic particles that blocked sunlight.
The Arctic Oscillation (AO)
A positive phase of the Arctic Oscillation (top) is associated with strengthening of winds circulating counterclockwise around the North Pole north of 55°N, that is, roughly in line with Moscow, Belfast, and Ketchikan, Alaska. In winter these winds pull more warm air from oceans to continents causing winter warming, and like a top spinning very fast, they hold a tight pattern over the North Pole and keep frigid air from moving south. Cool winds sweep across eastern Canada while North Atlantic storms bring rain and mild temperatures to Northern Europe. Drought conditions prevail over the Mediterranean region.
During the negative phase of the Arctic Oscillation (bottom), cool continental air plunges into the Midwestern United States and Western Europe while storms bring rainfall to the Mediterranean region. Credit: David W. J. Thompson, J. M. Wallace
Eruption of Mount Pinatubo, Philippines, July 1991
Strong explosive volcanic eruptions, like ones of the Mt. Pinatubo in Philippines in June 1991, inject millions of ton of sulfur dioxide gas at the altitudes of about 15 miles where it interacts with water vapor producing a volcanic aerosol layer that consists of tiny droplets of highly concentrated sulfuric acid.
As a result of the Pinatubo eruption, globally averaged surface temperature decreased by about 0.3 Kelvin (0.3 Celsius) for two years after the eruption and the temperature in the tropical lower stratosphere increased by about 2-3 Kelvin (2-3 Celsius). The tropospheric response over most land areas in the Northern Hemisphere is characterized by summer cooling and winter warming. Credit: U.S. Geological Survey, J.N. Marso, July 1991
One mission of NASA’s Earth Science Enterprise, which funded this research, is to better understand how the Earth system responds to human and naturally-induced changes, such as large volcanic eruptions.
“This study clarifies the effect of strong volcanic eruptions on climate, important by itself, and helps to better predict possible weather and short-term climate variations after strong volcanic eruptions,” said Georgiy Stenchikov, a researcher at Rutgers University’s Department of Environmental Sciences, New Brunswick, N.J., and lead author on a paper that appeared in a recent issue of the Journal of Geophysical Research.
Krishna Ramanujan | NASA/Goddard Space Flight Center
In times of climate change: What a lake’s colour can tell about its condition
21.09.2017 | Leibniz-Institut für Gewässerökologie und Binnenfischerei (IGB)
Did marine sponges trigger the ‘Cambrian explosion’ through ‘ecosystem engineering’?
21.09.2017 | Helmholtz-Zentrum Potsdam - Deutsches GeoForschungsZentrum GFZ
Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.
A warming planet
Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.
The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...
Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...
Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!
When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...
For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.
Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...
19.09.2017 | Event News
12.09.2017 | Event News
06.09.2017 | Event News
22.09.2017 | Life Sciences
22.09.2017 | Medical Engineering
22.09.2017 | Physics and Astronomy