Bites- Climate Change
Climate change grips Africa
Rising temperatures in Africa are blamed for droughts, floods and storms while the continent’s fabled wildlife is struggling to adapt to shifting ecosystems that could lead to mass extinctions. There has been an observable upward trend in temperatures in parts of Africa, for example in parts of eastern and central Africa and the Cape area, as well as emergent water shortages in western Chad and Darfur regions.
Expert say global warming may be to blame for the gradual melting of snow atop Tanzania’s famed Mt. Kilimanjaro. There is also an evidence that Lake Victoria, Lake Chad and parts of the Nile River are all gradually drying up due to warmer temperatures.
say, South Africa, the continent’s economic powerhouse, has
thus far failed to do much to address its own emission problems, a
poor example to other African countries. It is rated as Africa’s
largest emitter of harmful greenhouse gases, with the International
Energy Agency saying it released 318 million tones of carbon dioxide
in 2003. South Africa says it is committed to the fight against global
warming but the government’s desire to ramp up economic growth
has at times clashed with its environmental ideals.
Solar heating by atmospheric brown clouds
The RETREAT of the Himalayan-Hindu Kush glaciers is one of the major environmental problems facing Asia. These glaciers feed major river systems including the Indus, Ganges, Brahmaputra, Mekong, Yangtze and Huang He. The livelihood of over two billion Asians are affected by these rivers. The glacier retreat began in the mid-19th century in response to the termination of the mini Ice Age. The retreat has accentuated since the 1970s and includes major HHK glaciers such as Gangotri and over 90% of the Tibetan glaciers. Glaciologists link this acceleration to the large warming trend of about 0.25 degrees Celsius per decade that has been observed over the elevated Hindukush regions.
The prevailing understanding is that the warming trend is part of the global warming due to greenhouse gases. But several American and European scientists have speculated that solar heating by soot in Atmospheric Brown Clouds (ABCs) and deposition of dark soot over bright snow surfaces may also be important contributing factors.
IPCC concluded that as much as 50% of global warming due to man-made
greenhouse gases may have been masked by the dimming due to particles
in ABCs. The implication is that elimination of the brown clouds can
add another 0.8 degrees Celsius warming already observed during the
Migratory birds threatened
Disoriented by erratic weather, birds are changing migration habits and routes to adjust to warmer winters, disappearing feeding grounds and shrinking wetland.Failure to adapt, risks extinction. Birds face starvation when they arrive too early or too late to find their normal diet of insects, plankton or fish. In the north, some birds have stopped migrating altogether, leaving them at risk when the next cold winter strikes.
IPCC has warned in a series of reports this year that high emissions
of greenhouse gases are likely to raise the Earth’s average
temperatures by at least 3.6 degrees. The warning is predicted to
drive up to 30 percent of known animal species to extinction and migrating
birds are especially vulnerable. Climate change can strike at each
stage of their annual trek, from breeding ground to rest stops to
their final destination.Studies cited by the convention say arctic
permafrost and tundra where many species breed are melting. Even moderate
rises in sea levels can swamp wetlands where birds stop to feed.
Climate change can impact agriculture
Climate change is set to take a toll on Indian agriculture unless adaptive measures are put in place. There may be severe droughts at places and enhanced intensity of floods in other parts of the country, according to the secretary general of World Summit on Sustainable Development.
In the context of emerging scenario in the near future, Kutch and Saurashtra which occupies about one fourth of the area of Gujarat and 60% of Rajasthan may face acute water scarce conditions. River basins of Mahi, Pennar, Sabarmati and Tapti shall also face water shortage conditions. River basins belonging to Cauvery, Ganga, Narmada and Krishna shall experience seasonal or regular water-stressed conditions. River basins belonging to Godavari, Brahmani and Mahanadi shall not have water shortages but are predicted to face severe flood conditions.
The perennial sources of surface water would dry as the Himalayan glaciers that feed seven great Asian rivers- Ganga, Indus, Brahmaputra, Salween, Mekong, Yangtze and Huang Ho- were fast retreating.
It has been marked that 67% of glaciers are retreating at a startling rate in the Himalayas and the major casual factor has been identified as climate change.
The Khumbu Glacier, a popular climbing route to the summit of Mt.Everest, has retreated over 5 km from where Edmund Hillary and Tenzing Norgay set out to conquer the world’s highest mountain in 1953. The rate of retreat of the Gangotri glacier in the past three decades is three times higher than the rate for the previous 200 years.
melting of glaciers will cause an increase in river levels over the
next few decades, initially leading to higher incidence of flooding
and land-slides. But, in the longer term, as the volume of ice available
for melting diminishes, rivers will have lesser and lesser water.
In the Ganga, the loss of glacier meltwater would reduce July-September
flows by two thirds, causing water shortages for 500 million people
and 37% of India’s irrigated land.
Polar bears threatened as Arctic melts
Time may be running out for polar bears as global warming melts the ice beneath their paws. Restrictions or bans on hunting in recent decades have helped protect many populations of the iconic Arctic carnivore, but many experts say that long-term outlook is bleak.
An estimated 20,000 to 25,000 bears live around the Arctic- in Canada, Russia, Alaska, Greenland and Norway- and countries are struggling to work out ways to protect them amid forecasts of an accelerating thaw. There will be big reductions in numbers if the ice melts.
Many scientific studies project that warming, widely blamed on emissions of greenhouse gases from burning fossil fuels, could melt the polar ice cap in summer, with estimates of the break-up ranging from decades to sometime beyond 2100.
favourite hunting ground is the edge of the ice where they use white
fur as camouflage to catch seals. If there is no ice, there’s
no way they can catch the seal.
Heritage under threat…. Some facts..
The Sundarbans are the largest mangrove forests in the world, spread over 10,000 sq km of land and water. Mangroves are made up of salt-adapted evergreen trees restricted to the inter-tidal zone along the vast coastlines of tropical countries. They act as natural buffers against tropical cyclones and also as filtration systems for estuarine and freshwater. They also serve as nurseries for many marine invertebrate species and fish.
The Sundarbans mangrove forests are well-known for their biodiversity, including 260 bird species, Indian otters, spotted deer, wild boar, fiddler crabs, mud crabs, three marine lizard species and five marine turtle species. But they also host threatened species such as the estuarine crocodile, Indian python and the most iconic Bengal tiger.
According to the IPCC, sea level rise is the greatest threat and challenge for sustainable adaptation within south and southeast Asia. The consequences in terms of flooding of low lying deltas, retreat or shorelines, salinitisation and acidification of soils and changes in the water table raise serious concerns for the well-being of the local population.
The joint action of rise in sea-level, increased evapotranspiration and lower frehwater flow in winter will also result in increased salinity in the area threatening the conservation of the Sundarbans mangroves.
factors could lead, in the case of a 45 cm rise in global sea level,
to the destruction of 75% of the Sundarbans mangroves. Further destruction
of the Sundarbans mangroves would diminish their critical role as
natural buffers against tropical cyclones. About 10% of the world’s
tropical cyclones occur in this area and 17% hit Bangladesh. And exposure
of the region to the effects of storms will increase if the mangroves
are not conserved successfully.
The IPCC emphasizes that global warming will affect the oceans through changes in sea-surface temperature, sea-level, sea-ice cover, salinity, alkalinity, ocean circulation, and large-scale climate oscillations. Coastal ecosystems are sensitive to these physical and chemical changes, especially in relation to the increased level of flooding, loss of wetlands and mangroves and seawater intrusion into freshwater sources.
Great Barrier Reef, Australia
The Great Barrier Reef is the largest coral reef ecosystem in the world, covering an area of 344,400 sq km. The Great Barrier Reef Lagoon contain 2900 individual reefs with 400 species of corals, 1500 species of fish and several thousands species of mollusks. It also holds great scientific interest as the habitat of species such as the dugong(sea cow) and the green and loggerhead turtles, which are threatened with extinction.
The ecology of this World Heritage site is sensitive to climate parameters like sea-level rise, sea temperature increase, storm frequency and intensity, precipitation patterns, drought, land run-off, oceanic circulation and ocean acidity. One of the most dramatic and serious effects of observed and protected climate change is the physiological consequences of coral bleaching, which has already caused long trem damage to many coral reefs worldwide.
Coral reefs have a crucial role in shaping ecosystems. They are the primary habitat for hundreds of thoudands of species of fish and other organisms and the source of primary production in otherwise typically nutrient poor tropical oceans.
Overall, more frequent coral bleaching events will lead to less attractive reefs. In the long term, coral bleaching would reduce rates of coral reproduction, recruitment and calcification, resulting in an overall degradation of reef habitat.
At 5,895 M. Kilimanjaro is the highest mountain in Africa. This volcanic massif stands in splendid isolation above surrounding plains with its snowy peak looming over the savannah. The mountain is encircled by mountain forest. Numerous mammals, many of which are endangered species, live in the Park.The glaciers here have been persisting for over 10,000 years. As a result of the combined effect of global climate change and modification of local practices ( including changes of land use), they lost 80% of their area during the 20th century.
If the current trends are not inflected, losing more than half a meter in thickness each year will likely lead to the complete disappearence of the Kilimanjaro ice fields in less than 15 years. Glaciers in eight out of the nine European glacier regions are in retreat. Between 1850 and 1980, glaciers in the European Alps lost approximately one third of their area and one half of their mass, and since 1980 another 20 to 30% of the ice has melted.
During the 2003 heat wave, about 10% of European glacier mass melted. If this trend continues, by 2050, 75% of the glaciers in the Swiss Alps are likely to have disappeared. Glacier melting in the Alps will affect important European rivers such as the Rhine, the Rhone or the Danube and thus pose a threat to Europe’s fresh water supply. In the years to come, discharge from glacier melting will increase-possibly causing more frequent floods. But in the long term, with a widespread retreat of Alpine glaciers, some regions in Europe may face a decrease in freshwater supply.
RWAs fight battle against global warming in Delhi
The worldwide war against global warming has always been highlighted at high-powered platforms as the United Nations but now IPCC has just found a small yet formidable ally in India. Its is the capital’s RWAs.
association of around 20 Residents Welfare Associations in the Capital
have decided to, quite literally, drive home the point that wasting
electricity through age-old habits in daily life eventually brings
the doomsday of climate change a bit closer. They would like to start
the campaign by adopting the easiest approach to contribute to the
global war which is replacing incandescent bulbs with compact