Ecosystem state change in the Arabian Sea fuelled by the recent loss of snow over the Himalayan-Tibetan Plateau region.

The recent trend of global warming has exerted a disproportionately strong influence on the Eurasian land surface, causing a steady decline in snow cover extent over the Himalayan-Tibetan Plateau region. Here we show that this loss of snow is undermining winter convective mixing and causing stratification of the upper layer of the Arabian Sea at a much faster rate than predicted by global climate models. Over the past four decades, the Arabian Sea has also experienced a profound loss of inorganic nitrate.

Archaeal enrichment in the hypoxic zone in the northern Gulf of Mexico.

Areas of low oxygen have spread exponentially over the past 40 years, and are cited as a key stressor on coastal ecosystems. The world's second largest coastal hypoxic (≤ 2 mg of O2 l(-1)) zone occurs annually in the northern Gulf of Mexico. The net effect of hypoxia is the diversion of energy flow away from higher trophic levels to microorganisms.