Satellite Images of Houston Metro Area
These images show the Houston metropolitan area, where buildings, roads and other built surfaces create urban heat islands that can affect local rain patterns. The images were taken by ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer), an imaging instrument that is flying on Terra, a satellite launched in December 1999 as part of NASAs Earth Observing System (EOS). Credit: NASA/J
Higher Rainfall Rates Downwind of Texas Cities
This image shows areas where urban heat islands influenced higher rainfall rates (in blue) downwind of major cities connected by Interstate 35, known as the I-35 corridor in Texas. The winds that carried clouds and rainfall downwind (in this case, south and east of urban areas) occurred roughly 3.0 kilometers (1.9 miles) above the surface. Rainfall was measured by the precipitation radar instrument on NASAs Tropical Rainfall Measuring Mission (TRMM) satellite. The higher rainfall rates depicted here were derived from measurements of mean monthly rainfall during the warm seasons (May through September) from 1998 through 2000. Credit: Jim Williams, Scientific Visualization Studio, NASA/Goddard Space Flight Center
New evidence from satellites, models, and ground observations reveal urban areas, with all their asphalt, buildings, and aerosols, are impacting local and possibly global climate processes. This is according to some of the world’s top scientists convening in a special session at the Fall Meeting of the American Geophysical Union in San Francisco.
To study urban impact on local rainfall, Dr. J. Marshall Shepherd of NASA’s Goddard Space Flight Center, Greenbelt, Md., and Steve Burian of the University of Utah, Salt Lake City, used the world’s first space-based rain radar, aboard the Tropical Rainfall Measuring Mission (TRMM) satellite, and dense rain gauge networks on land to determine there are higher rainfall rates during the summer months downwind of large cities like Houston and Atlanta. Burian and Shepherd offer new evidence that rainfall patterns and daily precipitation trends have changed in regions downwind of Houston from a period of pre-urban growth, 1940 to 1958, to a post-urban growth period, 1984 to 1999.
Cities tend to be one to 10 degrees Fahrenheit (0.56 to 5.6 degrees Celsius) warmer than surrounding suburbs and rural areas. Warming from urban heat islands, the varied heights of urban structures that alter winds, and interactions with sea breezes are believed to be the primary causes for the findings in a coastal city like Houston.
Krishna Ramanujan | GSFC
Conservationists are sounding the alarm: parrots much more threatened than assumed
15.09.2017 | Justus-Liebig-Universität Gießen
A new indicator for marine ecosystem changes: the diatom/dinoflagellate index
21.08.2017 | Leibniz-Institut für Ostseeforschung Warnemünde
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...
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