A new study found that warmer rivers caused by climate change hasten the melting of ice in the Arctic sea. This episode led to the increased river flow in the region.
Researchers from NASA's NASA's Jet Propulsion Laboratory in Pasadena, led by senior research scientist Son Nghiem, examined the sea ice in the Beaufort Sea using the data from the Moderate Resolution Imaging Spectrodiameter (MODIS) instrument situated on the agency's Terra Satellite. They then compared it to the river flow of the Mackenzie River in western Canada.
Upon comparison, they discovered that a stretch of landfast sea ice acted as a barrier that suspended the river discharge close to its delta. After three weeks, they looked onto it again and found that the ice barrier disappeared. The water temperature also rose by 6.5 degrees Celsius (11.7 degrees Fahrenheit).
Landfast ice is what we call the stuck sea ice in the coastline.
Nghiem told Discovery News, "When the Mackenzie River's water is held back behind the sea ice barrier, it accumulates and gets warmer later in the summer. So when it breaks through the barrier, it's like a strong surge, unleashing warmer waters into the Arctic Ocean that are very effective at melting sea ice. Without this ice barrier, the warm river waters would trickle out little by little, and there would be more time for the heat to dissipate to the atmosphere and to the cooler, deeper ocean."
According to the researchers, warmer temperatures led to the Arctic ice melt, which in turn, melts the barriers of landfast ice. The melting of the landfast ice contributed to the increase in the volume of water in the river that flows into the Arctic sea.
Moreover, as the warming of the river contributes to earlier and greater melting of the Arctic's reflective ice cover in summer, the amount of solar heat absorbed into the ocean increases, which causes more sea ice to melt.
Further details on this study can be read on the journal Geophysical Research Letters.
