Researchers have found that melting snow caps in the Himalayas are leading to a spread of toxic green algae blooms large enough to be seen from outer space. The research used images taken by NASA as a reference in studying the blooms of the algae species Noctiluca scintillans, also known as 'sea sparkle'.
The lining coastlines along the Arabian Sea were found to be filled with the glowing green algae. Measuring approximately a millimeter in length, the planktonic organism can prosper in coastal waters and form thick green swirls and filaments.
Just twenty years ago, the buoyant glowing organism was unheard of. But now, it has been multiplying at an extremely alarming pace around India, Pakistan, and other areas in the Southeast Asian region.
Although intriguing to look at, especially at night, the sea sparkle blooms drive out plankton, which is fundamental to the Arabian Sea's food chain. The proliferation of the algae species threatens the plethora of fish swimming in the waters, as well as the continued activity of fisheries that sustain about 150 million people.
The research on sea sparkle and its effects on the environment has been published in Scientific Reports.
Global Warming Does it Again
According to researchers, the continued loss of snow over the Himalayan-Tibetan Plateau region is brining about Noctiluca's amplification by making ocean surfaces warmer.
Images coming from NASA's satellite associates the rise of Noctiluca in the Arabian Sea with a weakened winter monsoon and melting glaciers.
Joaquim Goes from Columbia University's Lamont-Doherty Earth Observatory said that the proliferation of sea sparkle is probably one of the most dramatic changes observed concerning climate change.
He adds that Noctiluca can now also be seen off the coasts of Thailand and Vietnam, even stretching out as far as Seychelles. Goes says that everywhere the algae blooms are becoming a problem as it harms the water quality and causes a lot of deaths among fishes.
Typically, cold winter monsoon winds blowing from the Himalayas cool the surface of the ocean waters. Once cooled, these waters sink and are replaced with nutrient-rich waters from below, which aid phytoplankton. Phytoplankton are the essential producers of the food chain.
However, the melting of glaciers and ice caps in the Himalayas makes the monsoon winds blowing from the land warmer and moister. This then agitates the process and leads to fewer nutrients at the water's surface. On the contrary, this benefits Noctiluca, since it doesn't rely on sunlight and nutrients. It can survive by consuming other organisms.
Noctiluca Scintillans and the Environment
Noctiluca's endosymbionts gather a lot of ammonia in Noctiluca's cell to carry nitrogen-rich nutrients but also make it unpalatable to larger creatures, such as fish.
Only jellyfish and salps, a translucent marine invertebrate, seem to find Noctiluca palatable.
Loss of fishery resources has the potential to further aggravate socio-economic trouble for countries in the region that are already dealing with war and poverty.
According to the researchers, the study provides new evidence of the impacts of global warming on the Indian monsoons.
Goes says that most studies connected to climate change and ocean biology are focused on the polar and temperate waters. He adds that changes in the topics are going significantly overlooked.