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Posts tagged Climate Change

Climate Change’s Impacts on Lake Poopó, Bolivia: Reduced Area and Biodiversity – July 1st, 2013

18.7S 67W

July 1st, 2013 Category: Climate Change, Image of the day, Lakes, Salt Flats VIIRSSuomi-NPP

Bolivia – June 28th, 2013

Visible high on the Bolivian altiplano are the green waters of Lake Poopó and the bright white surface of the Salar de Uyuni. Lake Poopó’s area has decreased by 50% in the last 25 years, with serious consequences for the populations of resident and migratory waterbirds.

The lake is located at approximately 3700 m above sea level, covering an approximate area of 967,000 ha, making it the second biggest lake in Bolivia, after Lake Titicaca (visible in the upper part of the full image), which is shared with Peru. However, in only 25 years its area has decreased by about 17,400 ha, representing almost 50% of its total area.

The decrease in the wetland’s area of open water has been attributed principally to climate change, which, in conjunction with current hydrological conditions (high rates of evaporation, low rainfall, and low flow rates of the rivers flowing into the lake), mean that water levels in the lake are not rising. This has had serious impacts on the biodiversity which depends on the wetland, given that the salinity has increased, thus decreasing survival rates of some species, with subsequent consequences in the local economy.

The change in size of the wetland has represented a considerable loss of available habitat for migratory bird species, for which the lake represents an important habitat, especially during the dry season (May to September), coinciding with the southern winter. However, drastic decreases in the populations of these species have been detected since 2007. Preliminary results suggest that the reason for this decline is the loss of available habitat as a result of the reduced area of Lake Poopó, and the accumulation of solid waste around the shores of the lake (click here for more information).


Climate Change Risks for Madeira Archipelago

32.7N 16.9W

June 25th, 2013 Category: Climate Change VIIRSSuomi-NPP

Canada – June 25th, 2013

Climate change can have severe effects on the natural environment, including water resources and ecosystems. Islands are unique systems more vulnerable to climate change than continental areas. Madeira, an Atlantic subtropical island (image center), has a quite unique flora and fauna and is considered a biodiversity ‘hot-spot’.

The lower altitudes of Madeira are predominantly occupied by urban areas and agricultural crops; exotic forest plantations are widespread at low- to mid-altitudes. The native forest, Laurissilva, an extremely important and rare ecosystem, occurs up to 1450 m and is replaced in higher altitudes by heaths and other altitude vegetation.

Future climatic scenarios project reduced rainfall and higher average temperatures across Madeira. The potentially suitable area for the main agricultural crops is expected to expand in altitude. Suitable area for the exotic forests and the Laurissilva is expected to increase as the expansion in altitude will be greater than the retraction in lower reaches.

The suitable climatic range for heaths will suffer a severe reduction: it is expected to retract in lower reaches but cannot expand in altitude because it is predominantly in the higher elevations already. These shifts in habitat distributions may translate into large changes in ecosystem services supply. Altitude species, including endemic and rare ones, may suffer range reductions or even disappear (click here for more information).

Climate Change’s Potential Effects on Coastal Florida

26.7N 82.1W

June 19th, 2013 Category: Climate Change VIIRSSuomi

USA – June 19th, 2013

Climate change poses a tremendous threat to Florida. Sea level rise, more intense precipitation, and stronger hurricanes increase the risk of natural disaster and imperil the state’s economy and its citizens’ safety. Compounding these dangers, increasing coastal population and development will put more people and property at danger. In years to come, those risks will lead to devastating damage if they are not mitigated.

One of the clearest impacts of climate change is the documented rise in sea levels, which has been taking place along Florida’s coasts at more than two centimeters per decade. Higher atmospheric temperatures heat the oceans and water expands as it warms. Sea levels rise further as melt waters from glaciers and continental ice sheets pour into the oceans at high latitudes. This process is expected to accelerate. Sea levels are projected to be three to seven inches higher by 2030 (over 2010), nine to 24 inches higher by 2060, and 39 inches higher by 2100, and the rise will continue long thereafter.

Even apart from larger storm surges, these sea level rises will have major impacts on coastal Florida, where 80 percent of the state’s population lives. Because so much of the shoreline is flat and low-lying, the impacts of even small rises extend far inland. Taking tidal variations into account, a one-foot rise can move the shoreline inward by more than a thousand feet. Most of this inundation will affect undeveloped land, especially in South Florida, replacing upland plant communities with mangroves and marshes and replacing those with tidal flats and open water. Commercial and recreational fisheries dependent on those coastal ecosystems and estuaries for spawning will be damaged along with many bird and animal populations

Falling Water Levels in the Salton Sea, USA – June 19th, 2013

33.2N 115.7W

June 19th, 2013 Category: Climate Change, Lakes MODISTerra

USA – June 17th, 2013

The Salton Sea is a victim of climate change and reduced quantities of water. The Salton Sea is (still) the largest lake of California. Lately, however, the water levels in the Sea have dropped with as much as 3 feet a year. Many fear that if nothing is done about it, there will be nothing left of the lake in a few decades.

This will cause new problems. Palm Springs, 35 miles north, fears dust storms of pesticide polluted salt particles. Environmentalists fear for the millions of migratory birds for whom this is the last remaining wetland in California. So far all initiatives to save the sea have failed. The Salton Sea is a perfect example of the choices that are made when the water runs out – the big cities and massive agricultural lands are priviledged (click here for more information).

The Role of Bering Strait in Regulating the Global Climate

65.4N 169.9W

June 18th, 2013 Category: Climate Change AVHRRMetOp

Russia and USA – June 17th, 2013

Alaska’s Bering Strait may play a critical role in the regulation of the global climate — including a knack for maintaining the Atlantic Ocean “conveyor belt” that bathes northern Europe in sultry currents and warm wet weather.

But squeeze shut the 53-mile-wide narrows between the Pacific and Arctic oceans off the western tip of Alaska — something that occurred during the last ice age when continental ice sheets locked up much of the world’s fresh water — and the oceanic engine that stabilizes the home planet’s climate becomes much more likely to go on the fritz and stay that way for a long time.

These resulting shutdowns have previously stalled the Gulf Stream and triggered abrupt swings between warmer and frigid climates, what scientists call Dansgaard-Oeschger and Heinrich events. These jarring shifts struck the North Atlantic as many as 25 times between 80,000 and about 11,000 years ago, all during moments when the Bering Land Bridge blocked all flow between Pacific and Arctic oceans.

The flow of the Gulf Stream and other elements of the global ocean circulation system deliver warm salty water to the North Atlantic, where it cools, grows denser, and sinks. At depth, this dense salty water starts flowing south. It then keeps rolling, eventually crawling into other hemispheres along a network of deep ocean currents that meander the globe over hundreds of years while equalizing the climate.

But introduce massive amounts of less dense fresh water into the mix, and the North Atlantic sinking starts to sputter, slowing the deep currents to the point where they temporarily die. The paradoxical result can be a chilldown of northern Europe and perhaps the entire northern hemisphere. Thus, smooth functioning of the Atlantic ocean “conveyor” becomes a “critical link” in keeping the world’s climate from making these wild swings (click here for more information).