Tiempo Climate Newswatch

The Twenty-Second Session of the Subsidiary Bodies to the United Nations Framework Convention on Climate Change continued this past week in Bonn, Germany, ending 27th May. Following lengthy negotiations, agreement on financial support for Least Developed Countries (LDCs) was reached and will be recommended to the Conference of the Parties later this year.

Bangladesh, speaking for the LDCs, described the final text as a compromise and called on the Global Environment Facility to operationalize the guidance in a way that truly responds to the need to implement the National Adaptation Programmes of Action. There had been considerable disagreement over whether or not responses to short-term climate variability should be supported as well as adaptation to long-term, anthropogenic climate change. The final wording side-steps the issue.

More information

• New Scientist
• ENN
• BBC
• Green Building Press

• Speech, Jurgen Trittin
• Live webcast, UNFCCC
• Daily coverage, ENB
• Press release, UNFCCC

A new climate model assessment predicts wetter conditions for the Sahel region of northern Africa but drier conditions across the south of the continent. The models predict that, under global warming conditions, temperature rises over the Atlantic Ocean will bring more rain to the Sahel. Whereas "in our models, the Indian Ocean shows very clear and dramatic warming into the future, which means more and more drought for southern Africa," reported Jim Hurrell of the National Center for Atmospheric Research in the United States.

The results are based on 60 climate simulations by five computer models. The Sahelian drought of the late 20th century is linked by the models to the cooling of the North Atlantic Ocean that occurred at the same time. "This was the situation during much of the latter half of the 20th century," according to Hurrell. "We believe the North Atlantic Ocean cooling was natural and masked an expected greenhouse-gas warming effect."

More information

• Eurekalert
• Forest Conservation portal

• Download draft research paper (1.1 Mb)
• Background on Sahel drought

The Brazilian rainforest may be absorbing less carbon as trees grow, and die, faster than before. Larger, quicker growing species are thriving at the expense of smaller trees below the forest canopy. The results have emerged from a 20-year study of the effects of human clearance. "It is clear that this is not random variation. Rainforest dynamics are changing," concludes project leader William Laurance of the Smithsonian Tropical Institute.

The trend showed up in areas where human activities, such as logging or burning, had not affected the forest directly. One possible explanation, though, is the complex response of the ecosystem as enhanced carbon dioxide in the atmosphere affects the rate of photosynthetic carbon uptake. "Increases in forest carbon storage may be slowed by the tendency of canopy and emergent trees to produce wood of reduced density as their size and growth rate increases, and by the decline of densely wooded sub-canopy trees," warns Laurance.

More information

• BBC

• Irish Examiner