2020-05-12. Aircraft spies gravity waves being sucked into Antarctica’s polar vortex. By Eric Hand, Science Magazine. Excerpt: The Southern Ocean is famously stormy, home to waves taller than telephone poles. Yet 50 kilometers overhead, the weather is just as tempestuous, if less obviously so. Powerful waves in the air break and crash, dumping energy into the stratosphere and disrupting winds that help control the climate. …Around the world, gravity waves often arise when winds shove air over a mountain range, although storms and jet streams can also touch them off. In each case, a parcel of air gets pushed up, and gravity pulls it down. It overshoots and bobs back up. When confined by overhead winds, the train of undulating air parcels plows ahead horizontally, leading to so-called lee waves that can shake up commercial flights. … Some gravity waves crash in the upper stratosphere, about 50 kilometers up, but most keep rising into the mesosphere, where they can be seen causing ripples in the fluorescent glow of air molecules 90 kilometers up. They are even thought to create giant bubbles of plasma in the ionosphere more than 200 kilometers up, halfway to the International Space Station, causing trouble for radio communications. …climate modelers struggle to take the waves into account. That’s not only because their sources are so variable, but also because their wavelengths of tens of kilometers can be smaller than the size of the grids that modelers break up Earth’s atmosphere into…. [https://www.sciencemag.org/news/2020/05/aircraft-spies-gravity-waves-being-sucked-antarctica-s-polar-vortex]
2019-08-14. When Does Weather Become Climate? By Oliver Bothe, Eos/AGU. [https://eos.org/opinions/when-does-weather-become-climate] Excerpt: Individuals and political organizations alike often define “climate” as climate scientist John Kennedy did on Twitter: “Practically speaking: weather’s how you choose an outfit, climate’s how you choose your wardrobe.” Meanwhile, the scientific literature rarely defines climate more specifically than as the “statistics of weather.” …Possibly the most common current definition is that from the Intergovernmental Panel on Climate Change’s (IPCC) Fifth Assessment Report, which distinguishes between “climate in a narrow sense…as the average weather…over a period of time ranging from months to…millions of years” and “climate in a wider sense” as “the state…of the climate system.” …Earth’s climate system includes its atmosphere, hydrosphere, cryosphere, biosphere, and lithosphere. Besides statistics, descriptions of the climate system’s behavior may employ thermodynamics and fluid dynamics, along with chemistry, electromagnetism, rheology, and plasma physics. …The American Meteorological Society defines weather as the “state of the atmosphere” at a specific time and emphasizes the minutes-to-days scale of its variations and how these variations influence life or a celestial body. …If weather on Earth takes place over minutes to days and the shortest climate timescale is monthly, we need a conceptual definition of the transition between weather and climate. The IPCC separates climate variability from the scales of “individual weather events.”….
2019-04-29. California Heat Waves Triggered by Pacific Thunderstorms. By Mary Caperton Morton, Eos/AGU. Excerpt: Californians looking to beat the heat this summer might want to keep an eye on the eastern Pacific and Indian Oceans. A new study has found a link between tropical thunderstorm activity and heat waves in California’s Central Valley. The culprit is a large-scale atmospheric circulation pattern called the Madden-Julian Oscillation (MJO), which moves from west to east in a series of phases across the tropical Indian and Pacific Oceans, often dumping heavy rain in its wake. Previous studies have shown that the MJO can influence winter weather in North America, bringing fluctuating temperature spells to the Midwest and Northeast, but the new study, published in Advances in Atmospheric Sciences, is the first to study the MJO’s effects on North America during the summer months, says corresponding author Richard Grotjahn of the University of California, Davis….
2018-12-28. Rise of carbon dioxide–absorbing mountains in tropics may set thermostat for global climate. By Paul Voosen, Science Magazine. [https://www.sciencemag.org/news/2018/12/rise-carbon-dioxide-absorbing-mountains-tropics-may-set-thermostat-global-climate] Excerpt: Many mountains in Indonesia and neighboring Papua New Guinea consist of ancient volcanic rocks from the ocean floor that were caught in a colossal tectonic collision between a chain of island volcanoes and a continent, and thrust high. Lashed by tropical rains, these rocks hungrily react with CO2 and sequester it in minerals. That is why, with only 2% of the world’s land area, Indonesia accounts for 10% of its long-term CO2 absorption. Its mountains could explain why ice sheets have persisted, waxing and waning, for several million years (although they are now threatened by global warming). Now, researchers have extended that theory, finding that such tropical mountain-building collisions coincide with nearly all of the half-dozen or so significant glacial periods in the past 500 million years. “These types of environments, through time, are what sets the global climate,” said Francis Macdonald, a geologist at the University of California, Santa Barbara, when he presented the work this month at a meeting of the American Geophysical Union in Washington, D.C. If Earth’s climate has a master switch, he suggests, the rise of mountains like Indonesia’s could be it….
2015-12-22. How Biofuels Can Cool Our Climate and Strengthen Our Ecosystems. By Evan H. DeLucia and Carl R. Woes, Earth & Space News (AGU). Excerpt: As the world seeks strategies to reduce emissions of carbon dioxide (CO2) into the atmosphere, bioenergy is one promising substitute for fossil fuels [Somerville et al., 2010]. Currently, the United States uses the starch component from roughly 40% of its corn harvest to produce ethanol for the transportation sector (see the National Agricultural Statistics Service website). …Replacing annual crops with perennial grasses such as miscanthus and switchgrass would pull carbon out of the atmosphere and return it to the ground (Figure 2). These crops allocate a large fraction of their biomass below ground in their root systems, and they can rapidly build up carbon stores in soil, reversing losses associated with frequent tillage, particularly on degraded or heavily tilled soils…. https://eos.org/features/how-biofuels-can-cool-our-climate-and-strengthen-our-ecosystems
2015-07-20. NASA Captures “EPIC” Earth Image. NASA Deep Space Climate Observatory satellite. Excerpt: A NASA camera on the Deep Space Climate Observatory [DSCOVR] satellite has returned its first view of the entire sunlit side of Earth from one million miles away…taken by NASA’s Earth Polychromatic Imaging Camera (EPIC), a four megapixel CCD camera and telescope. [This…is the first complete picture of our planet since 1972 (those in the interim have actually been composites). …DSCOVR [is] a joint mission between NASA, the National Oceanic and Atmospheric Administration, and the U.S. Air Force…. http://www.nasa.gov/image-feature/nasa-captures-epic-earth-image
2015-07-09. NASA Study Finds Indian, Pacific Oceans Temporarily Hide Global Warming. NASA Release 15-147. Excerpt: A new NASA study of ocean temperature measurements shows in recent years extra heat from greenhouse gases has been trapped in the waters of the Pacific and Indian oceans. Researchers say this shifting pattern of ocean heat accounts for the slowdown in the global surface temperature trend observed during the past decade. …”The western Pacific got so warm that some of the warm water is leaking into the Indian Ocean through the Indonesian archipelago,” said Nieves, the lead author of the study. The movement of the warm Pacific water westward pulled heat away from the surface waters of the central and eastern Pacific, which resulted in unusually cool surface temperatures during the last decade. Because the air temperature over the ocean is closely related to the ocean temperature, this provides a plausible explanation for the global cooling trend in surface temperature…. http://www.nasa.gov/press-release/nasa-study-finds-indian-pacific-oceans-temporarily-hide-global-warming
2010 August 26. NSF Press Release 10-154: Shrinking Atmospheric Layer Linked to Low Levels of Solar Radiation. Excerpt: Large changes in the sun’s energy output may drive unexpectedly dramatic fluctuations in Earth’s outer atmosphere.
Results of a study published today link a recent, temporary shrinking of a high atmospheric layer with a sharp drop in the sun’s ultraviolet radiation levels.
The research, led by scientists at the National Center for Atmospheric Research (NCAR) in Boulder, Colo., and the University of Colorado at Boulder (CU), indicates that the sun’s magnetic cycle, which produces differing numbers of sunspots over an approximately 11-year cycle, may vary more than previously thought.
…The findings may have implications for orbiting satellites, as well as for the International Space Station… The fact that the layer in the upper atmosphere known as the thermosphere is shrunken and less dense means that satellites can more easily maintain their orbits.
But it also indicates that space debris and other objects that pose hazards may persist longer in the thermosphere.
..The research indicates that the sun could be going through a period of relatively low activity, similar to periods in the early 19th and 20th centuries… This could mean that solar output may remain at a low level for the near future.
2010 August 14. In Weather Chaos, a Case for Global Warming. By Justin Gillis, The New York Times. Excerpt:…Far-flung disasters are reviving the question of whether global warming is causing more weather extremes.
…Theory suggests that a world warming up because of [greenhouse] gases will feature heavier rainstorms in summer, bigger snowstorms in winter, more intense droughts in at least some places and more record-breaking heat waves. Scientists and government reports say the statistical evidence shows that much of this is starting to happen.
…But the averages do not necessarily make it easier to link specific weather events, like a given flood or hurricane or heat wave, to climate change. Most climate scientists are reluctant to go that far, noting that weather was characterized by remarkable variability long before humans began burning fossil fuels and releasing greenhouse gases into the atmosphere.
…Climatologists have long theorized that in a warming world, the added heat would cause more record highs and fewer record lows… The statistics suggest that is exactly what is happening. In the United States these days, about two record highs are being set for every record low, telltale evidence that amid all the random variation of weather, the trend is toward a warmer climate.
…In general, the research suggests that global warming will worsen climate extremes across much of the planet. As in the United States, wet areas will get wetter, the scientists say, while dry areas get drier.
2009 August 9. Global warming could change Earth’s tilt. By Rachel Courtland, NewScientist. Excerpt: Warming oceans could cause Earth’s axis to tilt in the coming century, a new study suggests. The effect was previously thought to be negligible, but researchers now say the shift will be large enough that it should be taken into account when interpreting how the Earth wobbles.
The Earth spins on an axis that is tilted some 23.5° from the vertical. But this position is far from constant – the planet’s axis is constantly shifting in response to changes in the distribution of mass around the Earth. “The Earth is like a spinning top, and if you put more mass on one side or other, the axis of rotation is going to shift slightly,” says Felix Landerer of NASA’s Jet Propulsion Laboratory in Pasadena, California.
…The effect is relatively small. “The pole’s not going to drift away in a crazy manner,” Landerer notes, adding that it shouldn’t induce any unfortunate feedback in Earth’s climate.
But he says the motion is strong enough that it needs to be taken into account when interpreting shifts in Earth’s axis. Tracking the motion of the poles could help place limits on the total amount of sea level rise over decades….
2008 May 19. Study Says Global Warming Not Worsening Hurricanes. By THE ASSOCIATED PRESS. Excerpt: WASHINGTON (AP) — Global warming isn’t to blame for the recent jump in hurricanes in the Atlantic, concludes a study by a prominent federal scientist whose position has shifted on the subject. Not only that, warmer temperatures will actually reduce the number of hurricanes in the Atlantic and those making landfall, research meteorologist Tom Knutson reported in a study released Sunday.
… new study, based on a computer model, argues ”against the notion that we’ve already seen a really dramatic increase in Atlantic hurricane activity resulting from greenhouse warming.”
The study, published online Sunday in the journal Nature Geoscience, predicts that by the end of the century the number of hurricanes in the Atlantic will fall by 18 percent.
The number of hurricanes making landfall in the United States and its neighbors — anywhere west of Puerto Rico — will drop by 30 percent because of wind factors.
The biggest storms — those with winds of more than 110 mph — would only decrease in frequency by 8 percent. Tropical storms, those with winds between 39 and 73 mph, would decrease by 27 percent.
It’s not all good news from Knutson’s study, however. His computer model also forecasts that hurricanes and tropical storms will be wetter and fiercer. Rainfall within 30 miles of a hurricane should jump by 37 percent and wind strength should increase by about 2 percent, Knutson’s study says. …On the Net: Nature Geoscience: http://www.nature.com/naturegeoscience National Oceanic and Atmospheric Administration: http://www.noaa.gov/ ….
2008 January. High Peaks, Dirty Snow. By Allen Best, Forest Magazine, Winter 2008
The winter dust storms in Colorado’s San Juan Mountains have their own, somewhat predictable schedule. …Since they began documenting the storms several years ago, scientists have recorded up to eight dust storms per year among the mining towns of Telluride, Silverton and Ouray…. digging pits into the snowpack in the San Juan Mountains reveals something that is rather like an angel-food cake layered with chocolate. The “chocolate,” of course, is the dust, and it’s more than a mere oddity. Research conducted during the past several years has traced much of the dust to nearby deserts of the American Southwest. Some evidence already collected suggests that the relocation of the dust is not natural, but rather the result of disturbances of fragile desert soils in Arizona and New Mexico. Scientists studying sediments in high mountain lakes seek to determine whether such dust storms existed centuries ago, before livestock herding, four-wheeling and massive road building began in the Southwest. The working hypothesis is that today’s dust is something new.
What is clear is that the changing climate-warmer, with earlier springs-is causing the mountain snow to melt more rapidly across the
West. Peak runoff in springtime occurs three to four weeks earlier than it has in the recent past. New research in the San Juans points to the dust storms as causing additional acceleration of the melting, by about a month….Every child who has used black buttons to make the eyes of a snowman would know the principle, if not its name. Albedo is the extent to which a surface will reflect heat, i.e., solar energy. A darker surface will absorb the solar radiation, causing snow to melt faster and the button eyes to disappear. In this case, the albedo of the clean snow left it standing two to three inches above the darker, dirtier snow….the budding snow scientist, …Tom Painter …did … fully realize the potentially significant role of this vagrant dust in the hydrology of the mountain snowpack-and the further role it may play in causing the planet’s warming to accelerate….
Aug 2, 2004. RETREATING GLACIERS SPUR ALASKAN EARTHQUAKES In a new study, NASA and United States Geological Survey (USGS) scientists found that retreating glaciers in southern Alaska may be opening the way for future earthquakes. Goddard Space Flight Center
February 10, 2004 NASA PREDICTS MORE TROPICAL RAIN IN A WARMER WORLD (RELEASE: 04-058) As the tropical oceans continue to heat up, following a 20-year trend, warm rains in the tropics are likely to become more frequent, according to NASA scientists. … patterns of evaporation and precipitation, known as the water cycle, may accelerate in some areas due to warming temperatures.
JANUARY 11, 2003. ICESAT LAUNCH PLANNED — ICESat (Ice, Cloud, and land Elevation Satellite) is NASA’s Earth Observing System benchmark mission for measuring ice sheet mass balance, cloud and aerosol heights, as well as land topography and vegetation characteristics. It is planned to launch on January 11, 2003. The ICESat mission will provide multi-year elevation data needed to determine ice sheet mass balance as well as cloud property information, especially for stratospheric clouds common over polar areas. It will also provide topography and vegetation data around the globe, in addition to the polar-specific coverage over the Greenland and Antarctic ice sheets.
September 26, 2002 – BLACK CARBON CONTRIBUTES TO DROUGHTS AND FLOODS IN CHINA
June 21, 2001 NASA’S TERRA SATELLITE CAPTURES A WORLD OF SUNLIGHT AND HEAT (NASA RELEASE: 01-123)
Feb 2000. African Dust Leads to Large Toxic Algal Bloom [1.2MB PDF NASA Lithograph] Each year, several hundred million tons of African dust are transported westward over the Atlantic to the Caribbean, Gulf of Mexico, Central America, and South America. Thunderstorms and accompanying warm air can lift dust as high as 4575 meters (15,000 feet) above the African deserts, and then out across the Atlantic.