News ID: 4843
Publish Date:30 June 2018 - 09:21
Climate change takes center stage: 42% of islands in southern Iran could be underwater in 50 years
Climate change is threatening to swamp some 42 percent of the islands in the Persian Gulf, southern Iran, in as little as 50 years.
ECO-IEST: Climate change is threatening to swamp some 42 percent of the islands in the Persian Gulf, southern Iran, in as little as 50 years, Parvin Farshchi, the deputy head of the Department of Environment (DOE) for marine affairs has said.
The Persian Gulf is an extension of the Indian Ocean (Gulf of Oman) through the Strait of Hormuz and lies between Iran to the northeast and the Arabian Peninsula to the southwest.

Meanwhile, in an interview published in August 2017 in Khabaronline, Alireza Massah Bavani, associate professor at Department of Irrigation and Drainage Engineering, University of Tehran, explained that as the Persian Gulf and Sea of Oman are connected to international waters i.e. the Indian Ocean, sea rise level in the ocean can also affect the water level in the Persian Gulf as well. 

A paper in the Journal of Geophysical Research, published in 2016, shows that sea level rise in the northern Indian Ocean rose twice as fast as the global average since 2003. This represents a stark contrast to the previous decade, when the region experienced very little sea level rise at all.

The science team led by Philip Thompson, associate director of the University of Hawai'i Sea Level Center in the School of Ocean and Earth Science and Technology (SOEST), analyzed two and a half decades of ocean surface height measurements taken from satellites. The satellite data showed a substantial and abrupt increase in decade-long sea level trends in the Indian Ocean region, which prompted the oceanographers to investigate the cause of the shift using computer simulations of ocean circulation.

"Wind blowing over the ocean caused changes in the movement of heat across the equator in the Indian Ocean," said Thompson. "This led to suppression of sea level rise during the 1990s and early 2000s, but now we are seeing the winds amplify sea level rise by increasing the amount of ocean heat brought into the region."

Sea level rise a threat to the world

Over the past century, the burning of fossil fuels and other human and natural activities has released enormous amounts of heat-trapping gases into the atmosphere. These emissions have caused the Earth's surface temperature to rise, and the oceans absorb about 80 percent of this additional heat.

According to the National Geographic the rise in sea levels is linked to three primary factors, all induced by this ongoing global climate change:

Thermal expansion: When water heats up, it expands. About half of the past century's rise in sea level is attributable to warmer oceans simply occupying more space.

Melting glaciers and polar ice caps: Large ice formations, like glaciers and the polar ice caps, naturally melt back a bit each summer. In the winter, snows, primarily from evaporated seawater, are generally sufficient to balance out the melting. Recently, though, persistently higher temperatures caused by global warming have led to greater-than-average summer melting as well as diminished snowfall due to later winters and earlier springs. This imbalance results in a significant net gain in the ratio of runoff to ocean evaporation, causing sea levels to rise.

Ice loss from Greenland and West Antarctica: As with the glaciers and ice caps, increased heat is causing the massive ice sheets that cover Greenland and Antarctica to melt at an accelerated pace. Scientists also believe meltwater from above and seawater from below is seeping beneath Greenland's and West Antarctica's ice sheets, effectively lubricating ice streams and causing them to move more quickly into the sea. Higher sea temperatures are causing the massive ice shelves that extend out from Antarctica to melt from below, weaken, and break off.

When sea levels rise rapidly, as they have been doing, even a small increase can have devastating effects on coastal habitats. As seawater reaches farther inland, it can cause destructive erosion, wetland flooding, aquifer and agricultural soil contamination, and lost habitat for fish, birds, and plants.


Source: Tehran Times