Environment Forum

So long, sardines? Lake Tanganyika hasn’t been this warm in 1,500 years

lake_tanganyika1_hEast Africa’s Lake Tanganyika might be getting too hot for sardines.

The little fish have been an economic and nutritional mainstay for some 10 million people in neighboring Burundi, Tanzania, Zambia and the Democratic Republic of Congo — four of the poorest countries on Earth. They also depend on Lake Tanganyika for drinking water.

But that could change, according to research published in the online version of the journal Nature Geoscience. Using samples of the lakebed that chart a 1,500-year history of the lake’s surface water temperature, the scientists found the current temperature — 78.8 degrees F (26 degrees C) — is the warmest it’s been in a millennium and a half. And that could play havoc with sardines and other fish the local people depend on.

The scientists also found that the lake saw its biggest warm-up in the 20th century.

This unprecedented warm water could interfere with the lake’s unique ecosystem, which relies on nutrients churned up from the bottom of the lake to feed the algae that form the base of the lake’s food web. As Lake Tanganyika heats up, the mixing of waters is lessened and fewer nutrients get to the top level where algae and fish feed. More warming at the surface magnifies the difference between the two lake levels and even more wind is needed to churn the waters enough to get nutrients to the upper layer.

Some researchers believe declining fish stocks in Lake Tanganyika are due mainly to overfishing. However, climate change models show a general warming trend in the region, which would cause even greater warming of Lake Tanganyika’s surface. But in a statement from the U.S. National Science Foundation, which helped fund the research, scientists said that warming of the lake is making the decline in fish stocks worse, even if that is not the cause.

from Davos Notebook:

Africa feels the heat on climate change

kilimaIt may have contributed less than any other continent to CO2 emissions, but Africa is on the front line when it comes to the impact of climate change.

Just ask Tanzanian President Jakaya Kikwete.

"It is a threat for us," he told a panel at the World Economic Forum.  "On Kilimanjaro the snow is fast disappearing, sea levels are rising -- we have one island that has already been submerged -- and we've towns around the coast where we have to incur huge costs of adaptation to erect walls."

In theory, Africa is also in a strong position, given its virgin forests that represent one of the world's great carbon sinks. But setting up workable offset-trading schemes is easier said than done.  "I can assure you, it is so difficult to access these facilities," Kikwete said.

from Mario Di Simine:

Africans protest COP15, say “process manipulated”

In the most heated protest of these early days at COP15 in Copenhagen, African representatives accused the political leaders of the developed world of hijacking the conference to the detriment of developing nations.

The marchers said the process of the talks had been manipulated by the developed world's political leaders to impose on Africans a deal that won't benefit them.

Augustine Njmanshi, of Christian Aid, said Africans were suffering and would "not die in silence."

Solar heads to developing world

While solar power has investors on Wall Street seeing green, countries in the developing world also see a bright future in solar technology.

They believe solar power systems that convert sunlight into electricity can help power developing areas without going the route of dirty coal-fired power plants.

Solar companies like China’s solar panel maker Suntech and California-based eSolar, have recently announced forays into the developing world.

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