New NASA Space Observatory to Study Carbon Conundrums | NASA
El CO2 impulsa el aumento de medusas en el Mediterráneo
La concentración de ácido provocará pérdidas millonarias en el turismo y la industria pesquera
En las últimas tres décadas la concentración de ácido en el mar ha aumentado un 10%
DAVID GARCÍA VÁZQUEZ Barcelona 12 JUN 2014 - 13:59 CET
Ejemplar de rhizostoma pulmo, medusa típica del mar Mediterráneo. / C. ÁLVAREZ
Los mares y océanos son uno de los sumideros de carbono más grandes del planeta. Una trabajo fundamental para mitigar el cambio climático. La mitad del CO2 de origen antropogénico, aquel que no se produciría de no ser por la mano del hombre, se concentra en la atmósfera; la otra está almacenada entre los bosques y las masas de agua. Pero este secuestro de carbono de los mares y océanos está causando estragos en la biodiversidad submarina, ya que el dióxido de carbono se disuelve en contacto con el agua del mar transformándose en ácido. Solo en los últimos 30 años, la acidificación del Mediterráneo ha aumentado un 10%; y de mantenerse el nivel de emisiones de CO2 a la atmósfera, en las próximas cuatro décadas podría crecer un 30%, según revela el estudio MedSea, financiado por la Comisión Europea. Este proceso amenaza la biodiversidad del mar y la economía de sectores tan potentes en la región mediterránea como el turismo y la pesca por la reducción de peces y moluscos y el aumento de medusas.
A la acidificación mar se le une también el calentamiento del agua. El estudio asegura que en los últimos 25 años la temperatura del Mediterráneo ha aumentado 0,67 grados; y en 2050, "si no se implementan medidas para reducir las emisiones de carbono", lo hará entre 1 y 1,5 grados. "En los últimos años los procesos de acidificación y calentamiento del agua han sido rapidísimos", ha advertido Patrizia Ziveri, investigadora del Instituto de Ciencia y Tecnología Ambiental (ICTA) de la universidad Autónoma de Barcelona y coordinadora del estudio.
La combinación de aumento de las concentraciones de ácido y de la temperatura del agua afectará al fitoplancton y al zooplancton, base de la cadena trófica, por lo que gran cantidad de especies de peces verán amenazada su superviviencia. Los principales beneficiados de la merma en la población de peces son las medusas, que, además de perder a sus depredadores naturales, soportan mejor la acidificación y el calentamiento del agua. Un varapalo para las zonas turísticas. A falta de definir las conscuencias socioeconómicas en toda la región mediterránea, el estudio señala problemas locales. "Un brote de medusas en la costa de Israel podría reducir el número de viajeros entre un 3% y un 10,5%. Lo que provocaría unas pérdidas para la región de entre 2,4 y 4,6 millones de euros", apunta el estudio. Y en las Islas Medas (Girona), prosigue, la desaparición de las Gorgonias, una especie de alga, comportaría pérdidas por valor de cuatro millones de euros.
Según advierte el estudio, el impacto sobre las especies que viven en el Mediterráneo no será igual, ya que "los organismos presentan diferentes sensibilidades". Las praderas marinas y los arrecifes de coral son los ecosistemas que más sufren la acidifiación y el aumento de la temperatura del agua en el Mediterráneo. "Se trata de ecosistemas que construyen ecosistemas sorprendentes, que dan hogar de otros miles de especies, protegen la costa de la erosión y proporcionan comida y productos naturales a la sociedad", destaca el profesor Maoz Fine, de la universidad Ball-Ilan de Israel.
El texto pone de relieve la alta "sensibilidad" de algunas especies de los moluscos bivalvos (mejillones, ostras, almejas, etc.) al calentamiento del mar y al cambio en los niveles de PH, efecto directo de la acidificacióndel agua. "Ya hemos observado la alta mortalidad de estas especies cuando la temperatura del agua sube en verano", ha revelado Ziveri, que advierte: "La industria de la acuicultura de estas especies en el este del Mediterráneo de moluscos generó más de 225 millones de euros en 2012".
New NASA Space Observatory to Study Carbon Conundrums | NASA
New NASA Space Observatory to Study Carbon Conundrums | NASA
RELEASE 14-166
New NASA Space Observatory to Study Carbon Conundrums
Artist's rendering of NASA's Orbiting Carbon Observatory (OCO)-2, one of five new
NASA Earth science missions set to launch in 2014, and one of three managed by JPL.
Image Credit:
NASA-JPL/Caltech
NASA’s first spacecraft dedicated to measuring carbon dioxide levels in Earth’s atmosphere is in final preparations for a July 1 launch from Vandenberg Air Force Base, California.
The Orbiting Carbon Observatory-2 (OCO-2) mission will provide a more complete, global picture of the human and natural sources of carbon dioxide, as well as their “sinks,” the natural ocean and land processes by which carbon dioxide is pulled out of Earth’s atmosphere and stored. Carbon dioxide, a critical component of Earth’s carbon cycle, is the leading human-produced greenhouse gas driving changes in Earth’s climate.
“Carbon dioxide in the atmosphere plays a critical role in our planet's energy balance and is a key factor in understanding how our climate is changing,” said Michael Freilich, director of NASA’s Earth Science Division in Washington. “With the OCO-2 mission, NASA will be contributing an important new source of global observations to the scientific challenge of better understanding our Earth and its future."
NASA's Orbiting Carbon Observatory-2, launching July 2014, will study
carbon dioxide in the atmosphere and help us understand how fast it will build up in the future.
OCO-2 will launch on a United Launch Alliance Delta II rocket and maneuver into a 438-mile (705-kilometer) altitude, near-polar orbit. It will become the lead satellite in a constellation of five other international Earth monitoring satellites that circle Earth once every 99 minutes and cross the equator each day near 1:36 p.m. local time, making a wide range of nearly simultaneous Earth observations. OCO-2 is designed to operate for at least two years.
The spacecraft will sample the global geographic distribution of the sources and sinks of carbon dioxide and allow scientists to study their changes over time more completely than can be done with any existing data. Since 2009, Earth scientists have been preparing for OCO-2 by taking advantage of observations from the Japanese GOSAT satellite. OCO-2 replaces a nearly identical NASA spacecraft lost because of a rocket launch mishap in February 2009.
At approximately 400 parts per million, atmospheric carbon dioxide is now at its highest level in at least the past 800,000 years. The burning of fossil fuels and other human activities are currently adding nearly 40 billion tons of carbon dioxide to the atmosphere each year, producing an unprecedented buildup in this greenhouse gas.
Greenhouse gases trap the sun's heat within Earth's atmosphere, warming the planet’s surface and helping to maintain habitable temperatures from the poles to the equator. Scientists have concluded increased carbon dioxide from human activities, particularly fossil fuel burning and deforestation, has thrown Earth's natural carbon cycle off balance, increasing global surface temperatures and changing our planet's climate.
Currently, less than half the carbon dioxide emitted into Earth’s atmosphere by human activities stays there. Some of the remainder is absorbed by Earth’s ocean, but the location and identity of the natural land sinks believed to be absorbing the rest is not well understood. OCO-2 scientists hope to coax these sinks out of hiding and resolve a longstanding scientific puzzle.
“Knowing what parts of Earth are helping remove carbon from our atmosphere will help us understand whether they will keep doing so in the future,” said Michael Gunson, OCO-2 project scientist at NASA’s Jet Propulsion Laboratory (JPL), Pasadena, California. “Understanding the processes controlling carbon dioxide in our atmosphere will help us predict how fast it will build up in the future. Data from this mission will help scientists reduce uncertainties in forecasts of how much carbon dioxide will be in the atmosphere and improve the accuracy of global climate change predictions.”
OCO-2 measurements will be combined with data from ground stations, aircraft and other satellites to help answer questions about the processes that regulate atmospheric carbon dioxide and its role in Earth’s climate and carbon cycle. Mission data will also help assess the usefulness of space-based measurements of carbon dioxide for monitoring emissions.
The observatory's science instrument features three, high-resolution spectrometers that spread reflected sunlight into its component colors, then precisely measure the intensity of each color. Each spectrometer is optimized to record a different specific color absorbed by carbon dioxide and oxygen molecules in Earth’s atmosphere. The less carbon dioxide in the atmosphere, the more light the spectrometers detect. By analyzing the amount of light, scientists can estimate the relative concentrations of these chemicals.
The new observatory will dramatically increase the number of observations of carbon dioxide, collecting hundreds of thousands of measurements each day when the satellite flies over Earth’s sunlit hemisphere. High-precision, detailed, near-global observations are needed to characterize carbon dioxide's distribution because the concentration of carbon dioxide varies by only a few percent throughout the year on regional to continental scales. Scientists will analyze the OCO-2 data, using computer models similar to those used to predict the weather, to locate and understand the sources and sinks of carbon dioxide.
OCO-2 is a NASA Earth System Science Pathfinder Program mission managed by JPL for NASA's Science Mission Directorate in Washington. Orbital Sciences Corporation in Dulles, Virginia, built the spacecraft bus and provides mission operations under JPL’s leadership. The science instrument was built by JPL, based on the instrument design co-developed for the original OCO mission by Hamilton Sundstrand in Pomona, California. NASA's Launch Services Program at NASA's Kennedy Space Center in Florida is responsible for launch management. JPL is managed for NASA by the California Institute of Technology in Pasadena.
For more information about the Orbiting Carbon Observatory-2, visit:
and
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OCO-2 is the second of five NASA Earth science missions to be launched this year. NASA monitors Earth’s vital signs from land, air and space with a fleet of satellites and ambitious airborne and ground-based observation campaigns. NASA develops new ways to observe and study Earth’s interconnected natural systems with long-term data records and computer analysis tools to better see how our planet is changing. The agency shares this unique knowledge with the global community and works with institutions in the United States and around the world that contribute to understanding and protecting our home planet.
For more information about NASA's Earth science activities in 2014, visit:
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