Lago Titicaca puede secarse en unas décadas
Sequía catastrófica podría amenazar lago Titicaca para el 2050
Drought is on the horizon for the region surrounding Lake Titicaca; it may arrive by 2040
18 November 2010
Científicos del Global Change Biology (Biología del Cambio Global) y del Instituto de Tecnología de Florida han señalado que, de aumentar en 1.5 o 2 grados la temperatura de la tierra en los próximos años, el lago Titicaca podría convertirse en un amplio desierto.
Estos cambios podrían afectar, además, a diversas zonas de Bolivia, incluida La Paz, y algunas localidades peruanas. Los investigadores del Instituto de Tecnología de Florida llegaron a esta conclusión tras analizar los registros ecológicos históricos de los Andes. Éstos incluían los cambios durante 370.000 años en la vegetación y el clima de los ecosistemas andinos.
En BBC Mundo se brinda más información sobre el tema:
El análisis, llevado a cabo con polen fosilizado atrapado en los sedimentos del Lago Titicaca, reveló que durante dos de los últimos tres periodos interglaciares (el intervalo que separa a dos periodos glaciares), ocurridos hace entre 130.000 y 115.000 años y entre 330.000 y 320.000, el lago Titicaca (ubicado entre la frontera de Perú y Bolivia) se encogió 85%.Esto ocasionó que los prados y campos adyacentes se convirtieran en un desierto y que los árboles migraran cuesta arriba, afirman los investigadores.
“La evidencia de que hubo un súbito cambio hacia un estado mucho más seco, es clara” expresa el profesor Mark Bush, climatólogo que dirigió la investigación.
Según los investigadores, durante episodios de temperaturas moderadas los bosques tienden a migrar cuesta arriba.
Pero si el calentamiento continúa, el ecosistema es reemplazado por un nuevo estado más seco que detiene la expansión de los bosques.
“Si el lago se contrae, los efectos del clima local atribuibles a un lago más grande -como una mayor precipitación fluvial- se perderían” dice Mark Bush.
Los autores afirman que, dado el ritmo de calentamiento que ocurrido en los Andes peruanos -de entre 0,3 y 0,5 grados centígrados por década- el cambio a un estado desértico podría ocurrir entre el 2040 y 2050.
“Las implicaciones serían enormes para dos millones de personas” dicen los autores.
Una sequía severa y la pérdida del agua almacenada en los lagos de la región, reduciría la producción de regiones agrícolas importantes y amenazaría los abastecimientos de agua potables”.
Aunque estudios en el pasado ya han planteado la posibilidad de una severa sequía en la región, ésta es la primera vez que los científicos pueden establecer cuándo podría ocurrir ese cambio.
Lo cierto es que el calentamiento global viene afectando al Titicaca desde hace varios años. En este video -también publicado por BBC Mundo aunque en el año 2009- se daba cuenta de un descenso de 80 centímetros en el nivel de agua de este lago como producto del aumento de temperaturas del cambio climático. A estos factores se sumó, en esa ocasión, una prolongada sequía producto del fenómeno climático de El Niño.
Sequía catastrófica podría amenazar lago Titicaca para el - SPDA ...
18 Nov 2010 ... Sequía catastrófica podría amenazar lago Titicaca para el 2050 ... el lago Titicaca podría convertirse en un amplio desierto. ...
www.actualidadambiental.pe/?p=7872 - En caché
Lake Titicaca from space. Its outline may look very different in the future. Credit: NASA
Foreshadowing: in many years, nearby Lake Poopo has dried up but for brief periods. Credit: NASA
Drought is on the horizon for the region surrounding Lake Titicaca; it may arrive by 2040
November 12, 2010
Catastrophic drought is on the near-term horizon for the capital city of Bolivia, according to new research into the historical ecology of the Andes.
If temperatures rise more than 1.5 to 2 degrees Celsius (3 to 5 degrees Fahrenheit) above those of modern times, parts of Peru and Bolivia will become a desert-like setting.
The change would be disastrous for the water supply and agricultural capacity of the two million inhabitants of La Paz, Bolivia's capital city, scientists say.
The results, derived from research funded by the National Science Foundation (NSF) and conducted by scientists affiliated with the Florida Institute of Technology (FIT), appear in the November issue of the journal Global Change Biology.
Climatologist Mark Bush of FIT led a research team investigating a 370,000-year record of climate and vegetation change in Andean ecosystems.
The scientists used fossilized pollen trapped in the sediments of Lake Titicaca, which sits on the border of Peru and Bolivia.
They found that during two of the last three interglacial periods, which occurred between 130,000-115,0000 years ago and 330,000-320,000 years ago, Lake Titicaca shrank by as much as 85 percent.
Adjacent shrubby grasslands were replaced by desert.
In each case, a steady warming occurred that caused trees to migrate upslope, just as they are doing today.
However, as the climate kept warming, the system suddenly flipped from woodland to desert.
"The evidence is clear that there was a sudden change to a much drier state," said Bush.
Scientist Sherilyn Fritz at the University of Nebraska-Lincoln showed that during these warm episodes the algae living in Lake Titicaca shifted from freshwater species to ones tolerant of salty water. Paul Baker of Duke University identified peaks of carbonate deposition.
Both point to a sudden shallowing of the lake due to evaporative loss.
An environmental reconstruction demonstrates that with moderate warming, forests moved upslope. But as that warming continued, a climate tipping point was reached.
The system was thrown into a new, drier state that halted forest expansion.
The tipping point is caused by increased evaporative loss from Lake Titicaca.
As the lake contracts, the local climate effects attributable to a large lake--doubling of rainfall, among the most important--would be lost, says Bush.
Such tipping points have been postulated by other studies, but this work allowed the researchers to state when the system will change.
Based on the growth limits of Andean forests, they defined a tipping point that was exceeded within a 1.5 to 2 degrees Celsius warming above modern conditions.
Given a rate of warming in the Peruvian Andes of about 0.3-0.5 degrees Celsius per decade, the tipping point ahead would be reached between 2040 and 2050.
"The implications would be profound for some two million people," says Paul Filmer, program director in NSF's Division of Earth Sciences. Severe drought, and a loss of stored water in lakes in the region, would reduce yields from important agricultural regions and threaten drinking water supplies.
The research suggests that limiting wildfires would help delay the worst effects of the drought.
-NSF-
Lake Titicaca, and parts of Peru and Bolivia, are on the cusp of a major drought.
Credit: UNESCO
http://www.nsf.gov/news/mmg/media/images/drought_andes2_h.jpg
Saltbush pollen, the most common type of pollen during times of near-desert conditions. Atriplex is a plant genus of 100-200 species, known by the common names of saltbush and orache (or orach). ...Credit: Mark Bush/FIT
Atriplex (familia quenopodiacea) el tipo más común de polen durante la época de las condiciones casi desierto. El género Atriplex cubre especies potencialmente aprovechables en la agroforestería de las zonas altas y áridas de Bolivia.
[PDF]
Chenopodiaceae endémicas del Perú Formato de archivo: PDF/Adobe Acrobat - Vista rápida
de B León - 2006 - Artículos relacionados
trabajo reconocemos un endemismo en el género Atriplex. ... Palabras claves: Chenopodiaceae, Atriplex, Perú, endemismo, plantas endémicas. Abstract ...
sisbib.unmsm.edu.pe/bvrevistas/biologia/v13n2/pdf/a36.pdf
Pruebas de germinación y propagación vegetativa de especies de ...El género Atriplex cubre especies potencialmente aprovechables en la agroforestería de las zonas altas y áridas de Bolivia. Existen varias especies de ...
www.bensoninstitute.org/Publication/RELAN/.../Pruebas.asp
La investigación se ha desarrollado en los ambientes de invernadero y vivero de la Estación Experimental Patacamaya. La localidad de Patacamaya se encuentra en el Altiplano Central de Bolivia, cuyas coordinadas geográficas son 67º 55' latitud oeste y 17º 14' latitud sur. La temperatura promedio de la zona es de 11.2º C con precipitación anual de 360 mm, distribuida irregularmente en tres meses. Según la clasificación de zonas de vida propuesta por Holdridge, el Altiplano Central está catalogado como una formación estepa-montano-subtropical.
Para la investigación se han utilizado las siguientes especies y colecciones de Atriplex: 1) A. semibaccata recolectada de una introducción previa en Patacamaya. 2) A. cordobensis obtenida por intercambio de una introducción previa en Patacamaya. 3) A. numularia obtenida por intercambio de material genético. 4) A. halimus obtenida por intercambio de material genético. 5) A. Atriplex spp. pillagua proporcionada por N. Rodríguez - FAO Holanda. 6) A. Atriplex spp. luribay - A. rusbyi proveniente de una recolección propia.
http://www.nsf.gov/news/mmg/media/images/drought_andes4_h.jpg
nsf.gov - National Science Foundation (NSF) News - Catastrophic ...12 Nov 2010 ... Photo of a leafless tree on the shore of Lake Titicaca. ... appear in the November issue of the journal Global Change Biology. ...
www.nsf.gov/news/news_summ.jsp?cntn_id...org... -
Drought, Titicaca, Poopo, and Local Tipping Points | Watts Up With ...12 Nov 2010 ... Lake Titicaca, and parts of Peru and Bolivia, are on the cusp of a major .... Who even knew there was a journal Global Change Biology? ...
wattsupwiththat.com/.../drought-titicaca-poopo-and-local-tipping-points/ - En caché
Catastrophic Drought Looms For Capital City Of Bolivia | Before ...Lake Titicaca, and parts of Peru and Bolivia, are on the cusp of a major drought. ... Global Change Biology National Science Foundation ...
beforeitsnews.com/.../Catastrophic_Drought_Looms_For_Capital_City_Of_Bolivia.html
Catastrophic drought looms for capital city of Bolivia 14 Nov 2010 ... Both point to a sudden shallowing of the lake due to evaporative loss. ... The tipping point is caused by increased evaporative loss from Lake Titicaca. ... Global Change Biology, 2010; 16 (12): 3223 DOI: ...
www.sciencedaily.com/releases/2010/.../101112141332.htm
Nonlinear climate change and Andean feedbacks: an imminent turning ...de MB BUSH - Artículos relacionados
25 Feb 2010 ... Global Change Biology, no. doi: 10.1111/j.1365-2486.2010.02203.x ... from Lake Titicaca provides a detailed record of past climate change in ...
onlinelibrary.wiley.com/doi/10.1111/j.1365-2486.2010.02203.../abstract
Lake Titicaca | savingwater.co.za 15 Nov 2010 ... Lake Titicaca may shrink by as much as 85 percent ... Technology (FIT), appear in the November issue of the journal Global Change Biology. ...
www.savingwater.co.za/tag/lake-titicaca/ - En caché
New research predicts catastrophic droughts in the Central Andes ...10 Nov 2010... and published in the Global Change Biology journal. ... using fossilised pollen trapped in the sediments of Lake Titicaca, Peru/Bolivia. ...
www.open.ac.uk/.../new-research-predicts-catastrophic-droughts-central-andes - En caché
Global Warming Brings Drought to Highland Peru - The Cutting Edge ...17 Nov 2010 ... Latin American Topics - Lake Titicaca ... Institute of Technology (FIT), appear in the November issue of the journal Global Change Biology. ...
www.thecuttingedgenews.com/index.php?article...28... - En caché
Catastrophic Drought Looms for Capital City of Bolivia17 Nov 2010 ... Lake Titicaca from space. Its outline may look very different in the future. ... in the November issue of the journal Global Change Biology. www.terradaily.com/.../Catastrophic_Drought_Looms_for_Capital_City_of_Bolivia_999.html
Catastrophic drought looms for capital city of Bolivia | e ...12 Nov 2010 ... This is Lake Titicaca viewed from space. ... of Technology (FIT), appear in the November issue of the journal Global Change Biology. ...
esciencenews.com/.../catastrophic.drought.looms.capital.city.bolivia - En caché
Stacey says:
In the following article Paul Hudson discusses a study by Newcastle University wherby they determine that flooding is increasing due to global warming. Mr Hudson points out that Phillip Eden draws attention that the time period is too short and hence qustions the validity of the study?
Is this usual in self named climate science?
http://www.bbc.co.uk/blogs/paulhudson/2010/11/is-the-perceived-rise-in-flood.shtml#comments
steveta_uk says:
Off Topic:
Report: Global Warming Issue From 2 Or 3 Years Ago May Still Be Problem
(http://www.theonion.com/articles/report-global-warming-issue-from-2-or-3-years-ago,18431/)
ends with this:
“Climate change is real, and we are killing our planet more every day,” said climatologist Helen Marcus, who has made similar statements in interviews in 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, and 2010. “We need to make a serious effort to stop it, or, you know, we’ll all die. There really isn’t much else to say.”
---
