Mais evidência:
"The data on Lake Baikal reveal "significant warming of surface waters and long-term changes in the food web of the world's largest, most ancient lake," write the researchers in their paper.
"Increases in water temperature (1.21°C since 1946), chlorophyll a (300 percent since 1979), and an influential group of zooplankton grazers (335 percent since 1946) have important implications for nutrient cycling and food web dynamics."
The scientists conclude that the lake now joins other large lakes, including Superior, Tanganyika and Tahoe, in showing warming trends. "But," they note, "temperature changes in Lake Baikal are particularly significant as a signal of long-term regional warming. "This lake was expected to be among those most resistant to climate change, due to its tremendous volume and unique water circulation."
Aditamento 
"Mean dissolved oxygen concentrations in the world's oceans at a depth of 400 meters (1,312 feet) with blue contours representing the lowest concentrations. Boxed areas represent ocean regions analyzed in the study. Credit: AAAS/Science"
Mais evidência?
"The researchers found through analysis of a database of ocean oxygen measurements that levels in tropical oceans at a depth of 300 to 700 meters (985 to 2,300 feet) have declined during the past 50 years. The ecological impacts of this increase could have substantial biological and economical consequences.
“We found the largest reduction in a depth of 300 to 700 meters (985 to 2,300 feet) in the tropical northeast Atlantic, whereas the changes in the eastern Indian Ocean were much less pronounced,” said Stramma. “Whether or not these observed changes in oxygen can be attributed to global warming alone is still unresolved. The reduction in oxygen may also be caused by natural processes on shorter time scales.”
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