The Bahamas secured two medals at the 21st Pan American Under-20 (U20) Track and Field Championships which was held at the Jose A. Figueroa Freire Stadium in Mayaguez, Puerto Rico, this past weekend. Action got underway on Friday and wrapped up on Sunday. The Bahamas finished sixth in the medal standings with three total medals
Credit: Roel Brienen
For the first time scientists have provided clear evidence that tropical tree lifespan decreases above a critical temperature threshold.
Findings, published today (14 December) in the journal
PNAS (Proceedings of the National Academy of Sciences) show that across the tropics, tree lifespans decrease for temperatures above 25 C.
As temperatures are rising rapidly across large parts of the tropics, tree mortality is likely to accelerate in substantial parts of the tropics, including the Amazon, Pantanal and Atlantic forests with implications for animal habitats, air quality and carbon stocks.
Although tropical rainforests account for only 7% of all land, they are home to about 50% of all animal and plant species, and approximately 50 % of forest carbon stocks on earth. Thus small changes in the functioning of tropical forests can significantly change the atmospheric levels of CO2 - the most important anthropogenic greenhouse gas.