WASHINGTON, May 17 (Xinhua) -- Surface waters in Lake Tanganyika, the second-oldest and second-deepest lake in the world, are currently warmer than at any time in the previous 1,500 years, according to a study published in this week's on-line issue of the journal Nature Geoscience.
That finding is important, the scientists state, because the warm surface waters likely will affect fish stocks upon which millions of people in the region depend.
"This result is in addition to those from other African lakes showing that changes in regional climate have a significant impact on the lakes, and on the human populations that depend on the lakes' resources," said Paul Filmer, program director in the U.S. National Science Foundation's Division of Earth Sciences, which funded the research.
The scientists took core samples from the lakebed that laid out a 1,500-year history of the lake's surface temperature.
The resulting data showed that the lake's surface temperature, 26 degrees Celsius (78.8 F), last measured in 2003, is the warmest the lake has been for a millennium and a half.
The team also documented that Lake Tanganyika experienced its largest temperature change in the 20th century. The change has affected its unique ecosystem, which relies upon nutrients from the depths to jumpstart the food chain on which fish survive.
