Tag Archives: climate

Hacking Code of Leaf Vein Architecture Solves Mysteries, Allows Predictions of Past Climate

By Guest PostMay 27, 2012Environment, Natureancient greeks, carbon dioxide, christine scoffoni, climate, conifers, cycads, Environment, ferns, flowering plants, fossil record, global ecology, hacking code, images of leaves, lawren sack, leaf fossils, leaf sizes, leaf vein architecture, leaf vein systems, mathematical equation, mathematical linkages, michael rawls, past climate, photosynthesis, photosynthetic rate, plants, prediction, respiration, scaling patterns, superhighways, theophrastus of lesbos, tropical forest tree, ucla life scientists, vein network, water transport, xylem pipes

UCLA life scientists have discovered new laws that determine the construction of leaf vein systems as leaves grow and evolve. These easy-to-apply mathematical rules can now be used to better predict the climates of the past using the fossil record.

The research, published May 15 in the journal Nature Communications, has a range of fundamental implications for global ecology and allows researchers to estimate original leaf sizes from just a fragment of a leaf. This will improve scientists’ prediction and interpretation of climate in the deep past from leaf fossils.

Leaf veins are of tremendous importance in a plant’s life, providing the nutrients and water that leaves need to conduct photosynthesis and supporting them in capturing sunlight. Leaf size is also of great importance for plants’ adaptation to their environment, with smaller leaves being found in drier, sunnier places. (more…)

Study Finds Surprising Arctic Methane Emission Source

By Guest PostApril 22, 2012Environmentarctic methane, arctic ocean, arctic region, Arctic sea ice, arctic tundra soil, beaufort seas, carbon monoxide, chukchi, climate, concentration, earth system, eric kort, geologic reservoir, global warming, greenhouse gas, harvard university, hippo, jet propulsion laboratory, marine sediment, methane, NASA, ozone, reservoir, water vapor

The fragile and rapidly changing Arctic region is home to large reservoirs of methane, a potent greenhouse gas. As Earth’s climate warms, the methane, frozen in reservoirs stored in Arctic tundra soils or marine sediments, is vulnerable to being released into the atmosphere, where it can add to global warming. Now a multi-institutional study by Eric Kort of NASA’s Jet Propulsion Laboratory, Pasadena, Calif., has uncovered a surprising and potentially important new source of Arctic methane: the ocean itself. (more…)

800-Year-Old Farmers Could Teach Us How to Protect The Amazon

By Guest PostApril 14, 2012Environmentagriculture, Amazon, amazonian forest, amazonian savannas, archaeologist, cattle ranching, charcoal, climate, columbian encounter, conservation, deforestation, doyle mckey, ecosystem, Environment, european settlers, farming, farmland sustainably, fire, francis mayle, french guiana, global warming, indigenous people, jose iriarte, mitchell power, old world diseases, paleoecologist, phytoliths, plant remains, pollen, raised field, savannas, stephen rostain, sustainable use, university of exeter, university of montpellier

In the face of mass deforestation of the Amazon, we could learn from its earliest inhabitants who managed their farmland sustainably.

Research from an international team of archaeologists and paleoecologists, published in the journal Proceedings of the National Academy of Sciences, shows for the first time that indigenous people, living in the savannas around the Amazonian forest, farmed without using fire.

Led by the University of Exeter, the research could provide insights into the sustainable use and conservation of these globally-important ecosystems, which are being rapidly destroyed. Pressure on the Amazonian savannas today is intense, with the land being rapidly transformed for industrial agriculture and cattle ranching.

By analysing records of pollen, charcoal and other plant remains like phytoliths spanning more than 2,000 years, the team has created the first detailed picture of land use in the Amazonian savannas in French Guiana. This gives a unique perspective on the land before and after the first Europeans arrived in 1492. (more…)

Thawing Permafrost 50 Million Years Ago Led To Warm Global Events, Says New Study

By Guest PostApril 7, 2012EnvironmentAntarctica, arctic permafrost, carbon, climate, climatic threshold, CO2, earth, eccentric orbits, ecosystem, Environment, floor sediment, fossil fuel, frozen-soil, greenhouse gas levels, italy, kevin schaefer, methane gas, ocean, orbit, organic matter, paleocene eocene, permafrost, permafrost thaw, petm, rob deconto, soil, source, thermal maximum, university of urbino

A new study led by the University of Massachusetts Amherst and involving the University of Colorado Boulder proposes a simple new mechanism to explain the source of carbon that fed a series of extreme warming events on Earth about 50 million years ago called the Paleocene-Eocene Thermal Maximum, or PETM, as well as a sequence of similar, smaller warming events afterward.

“The standard hypothesis has been that the source of carbon was in the ocean in the form of frozen methane gas in ocean-floor sediments,” said lead study author Rob DeConto of the University of Massachusetts Amherst. “We are instead ascribing the carbon source to the continents in polar latitudes where permafrost can store massive amounts of carbon that can be released as CO2 when the permafrost thaws.” (more…)

Study of Patagonian Glacier’s Rise and Fall Adds to Understanding of Global Climate Change

By Guest PostMarch 24, 2012Environment17th century, andes, antonio de vea, chilean glacier, climate, climate change, climate system, earth, fernando torrejon, fluctuation, glacial environment, glacial melt, glacier, glacier fluctuation, glaciomarine sediment, global temperature, golfo elefantes, gualas glacier, holocene glacier, icebreaker, marine environment, nathaniel b palmer, neoglacial fluctuation, northern patagonian icefield, past temperature, patagonia, patagonias fjords, rainfall data, san rafael, sebastien bertrand, sediment record, spanish explorers, university of ghent, voyages, whoi

Glaciers play a vital role in Earth’s climate system, and it’s critical to understand what contributes to their fluctuation.

Increased global temperatures are frequently viewed as the cause of glacial melt, but a new study of Patagonia’s Gualas Glacier highlights the role of precipitation in the glacier’s fluctuation. The study, conducted by Sébastien Bertrand of the Woods Hole Oceanographic Institution (WHOI) and his colleagues, reconstructs a 5,400 year-record of the region’s glacial environment and climate, comparing past temperature and rainfall data with sediment records of glacier fluctuations and the historical observations of early Spanish explorers. (more…)

Mesquite Trees Displacing Southwestern Grasslands

By Guest PostMarch 21, 2012Environment, Natureatmosphere, biochemical pathway, bouteloua eriopoda, carbon dioxide, catalina mountains, changing climate, climate, climate data, desert, ecohydrology, ecosystems, eddy covariance tower, grama grass, grassland, greg barron gafford, groundwater, groundwater pool, mesquite tree, muhlenbergia porter, muhly, photosynthesis, predictions, prosopis velutina, rainfall, root system, san pedro river riparian area, santa rita mountains, seasonal precipitation, southeastern arizona, southwest, southwestern climate, sugars, temperature, university of arizona, warming climate, water resource, woody shrub

Mesquite trees and woody shrubs are better adapted than grasslands to a Southwestern climate predicted to shift toward higher temperatures and greater variability in rainfall, UA ecologists have discovered.

As the desert Southwest becomes hotter and drier, semi-arid grasslands are slowly being replaced by a landscape dominated by mesquite trees, such as Prosopis velutina, and other woody shrubs, a team of University of Arizona researchers has found.

In a “leaf-to-landscape” approach, the team combined physiological experiments on individual plants and measurements across entire ecosystems to quantify how well grasslands, compared to mesquite trees and woody shrubs, cope with heat and water stress across seasonal precipitation periods. (more…)

Confidence in Climate Data: Using 3 Million-Year-Old Records

By Guest PostMarch 20, 2012Uncategorized21st century, ar5, atmospheric co2, China, climate, climate conditions, fossils, france, geologic period, Germany, global warmth, ipcc, Japan, marci robinson, marcia mcnutt, million years, north atlantic climate, north atlantic data, norway, pliocene, pliocene conditions, pliocene temperature, pliomip, test models, trace gases, united kingdom, united states, university of bristol, university of leeds

How do we understand what’s happening today by looking back millions of years?

Scientists are looking at what climate conditions were like 3.3 to 3 million years ago, during a geologic period known as the Pliocene, and they are confident in the accuracy of their data.

The Pliocene is the most recent period of sustained global warmth similar to what is projected for the 21^st century. Climate during this time period offers one of the closest analogs to estimate future climate conditions. (more…)

Sailing in a Sea of Microbes

By Guest PostMarch 4, 2012Sciencealgae, Arctic, atmospheric chemistry, bacteria, biogeochemical cycles, biomass, carbon dioxide, Chile, climate, daniel stolte, easter island, Environment, food production, genome, Germany, global warming, grassroots initiative, greenhouse gas, matt sullivan, melissa duhaime, microbe, ocean water, oceans, oxygen production, pacific ocean, research vessel, saguaro cacti, sequence, tara oceans, ua, university of arizona, wolves, world of viruses, world of webs

Researchers led by Matt Sullivan at the UA are among the first to dive into the world of viruses drifting through the world’s oceans.

Surrounded by the deep blue of the Pacific Ocean stretching from horizon to horizon, a lonely dot is glinting in the sun. It is the aluminum hull of a sailboat, a 118-foot schooner with white sails billowing from two masts.

On the deck, crewmembers and scientists are milling about. Commands are flying back and forth, and soon a strange contraption consisting of tubes clustered around an array of sensors dangling from a crane is lowered into the water, until it disappears in the clear blue depths. (more…)