A group of scientists found evidence that the Antarctic sea-ice sheet is not melting due to climate change. It is actually spreading, and it has been doing so since 2000. Gerald A. Meehl, lead author of the paper, and his colleagues theorize that the findings could be a direct result of the Interdecadal Pacific Oscillation.
The natural phenomena could explain why the waters of the ocean are cooling off when a lot of scientists have been warning people about climate change melting the ice on the planet.
A team of specialists from the National Center for Atmospheric Research in Colorado analyzed the satellite records of the Antarctic sea-ice. The images go way back to 1979, and all the climate models scientists have created show a rise in the temperatures and the melting of ocean ice. That is why Meehl’s team was shocked after studying the pictures. According to what they saw, the ice in the Antarctic sea is spreading since 2000, and the pace has been growing exponentially since then.
“Since the late 1990s, the increase has accelerated, but the average of all climate models shows a decline,” reads the paper.
To make predictions about weather and climate, the scientists used complex equipment to complement the knowledge accumulated throughout the centuries and then, establish a series of patterns. However, nature does not follow linear processes, and scientists have found variables that can change the profiles in a radical way.
Scientists will have to revisit the climate change models created so far
The researching team theorizes that one of these variables is responsible for the expansion of ice in the Antarctic sea. It is called the Pacific Decadal Oscillation, and it was first noticed by Steven R. Hare when he was studying salmon reproduction patterns back in 1997. The natural phenomena cause a significantly changes the climate in the oceanic atmosphere in the Pacific Basin, which is the biggest of them all altering the ecosystems of all the island in the Pacific Rim.
To put it into simple words, the Pacific Decadal Oscillation happens when hot and cold water in the ocean suddenly change positions which substantially alters the climate in different areas. Scientists realized the phenomena has two stages. During the active, also known as warm, phase the west Pacific cools off while eastern oceans heat up, and during the negative phase, the exactly opposite occurs. According to the records, this has happened at least three times in the last 100 years, 1925, 1947 and 1977 respectively.
“The Interdecadal Pacific Oscillation, an internally generated mode of climate variability, transitioned from positive to negative, with an average cooling of tropical Pacific sea surface temperatures, a slowdown of the global warming trend and a deepening of the Amundsen Sea Low near Antarctica that has contributed to regional circulation changes in the Ross Sea region and expansion of sea ice,” reads the paper.
The researching team also noted the Antarctic sea-sea is not only increasing, but its growth accelerated each year from 2000 to 2014. The researchers think that such a drastic change is the result of a combination of factors. They believe that other variables from different parts of the Earth are playing a huge role in what the satellite images show.
“These atmospheric circulation changes are shown to be mainly driven by precipitation and convective heating anomalies related to the Interdecadal Pacific Oscillation in the equatorial eastern Pacific, with additional contributions from convective heating anomalies in the South Pacific convergence zone and tropical Atlantic regions,” the researchers wrote in the paper.
It could give humanity more time to work on environmental solutions
Climate change is as real as the consequences it brings. Many people underestimate the damage it would cause, but the scientists have not been shy about them. As a result, governments from all around the world, especially first world countries like the United States and Germany, have been cooperating with different organizations and created agencies to develop green policies.
According to the paper, the decrease of temperature in the oceans delays the effects of the greenhouse gasses and general global warming. This, combined with other variabilities identified in South Seas, could give people the chance to develop further and apply legislation to reduce the impact of climate change in human societies.
Gerald A. Meehl and his colleagues started analyzing the data last year, and first presented their work on February 26, 2016. After peer revision, the paper was finally accepted in May, and later it was on-line published in the journal Nature Geoscience on July 4, 2016.
Source: Nature