Greenland’s melting ice sheets and rising sea levels
Photo by Kathryn Hansen (NASA)
by Holly Leslie
Two-thirds of the earth’s surface is covered in water, either frozen or liquid. According to NASA, global temperatures have risen by 0.8 °C since 1880, with 2016 being documented as the warmest year on record. Recent reports suggest that in the months of July and August this year, Greenland lost 55 billion tons of ice over 5 days, which is enough to cover the state of Florida. The latest IPCC report suggests that greenhouse gases need to be cut by 30% to prevent melting of the earth’s most northern ice sheets, which would otherwise cause vast human displacement. The report also highlights that increasing global CO2 levels will lead to increased acidity of our oceans, which compromises marine life.
Current predictions warn of a 3-5οC increase by the turn of the century, according to the World Meteorological Organization (WMO). Increases in global temperature have been attributed to what scientists call the ‘greenhouse effect’ which describes the ability of atmospheric CO2 to absorb heat and release it back to the earth’s surface. This causes temperatures to rocket, ice caps to melt, sea levels to rise and weather systems to be disturbed. Furthermore, an increase in global temperature is predicted to increase the thawing rate of permafrost, encouraging unknown volumes of carbon dioxide to be released from the soil. Scientists warn that limiting global warming to < 1.5 οC, as pledged in the 2015 Paris Agreement, would require cutting CO2 emission by 45% by 2030 and reaching net-zero emission by 2050.
Michael Oppenheimer, a climate scientist and author of the UN Special Report on the Ocean and Cryosphere in a Changing Climate warns “there’s no scenario that stops sea level rise in this century. We’ve got to deal with this indefinitely”. The same report states that sea levels are currently rising at an increased rate and that extreme sea-level events are predicted to occur at least once per year (previously once per century) by 2050, particularly in tropical regions.
“there’s no scenario that stops sea level rise in this century. We’ve got to deal with this indefinitely”.
Greenland and Antarctica have been reported to hold more than 99% of the world's freshwater in their ice sheets, according to the National Snow and Ice Data Center. Scientist Andy Aschwanden, lead author and research associate professor at the University of Alaska Fairbanks’ Geophysical Institute, predicts that if no major reduction of our carbon footprint occurs, Greenland will be lost within the next century. Complete loss of Greenland’s ice sheets would lead to a global sea-level rise of 7 metres, not including the volume of ice melting in Antarctica. Furthermore, water expands when it warms making it hard to accurately predict the total rise in global sea level. Areas that are at particularly high risk of flooding over the course of the century include Bangladesh and eastern England.
Ongoing research led by Dr Masashi Niwano, a researcher with the Japan Meteorological Agency, aims to minimise unforeseen effects of climate change and enable vulnerable communities to prepare any adverse weather conditions. Environmental organisations continue to study the effects of global warming in extreme landscapes, such as Greenland, where an ice sheet, seven times the size of the UK, resides. Researchers in Greenland warn that whilst planting 6,000 saplings of Siberian larch may be a great start-up project in tackling climate change, a worldwide effort to replace forestland and conserve natural habitats is needed to "make a dent" in climate change.
The next IPCC report, due for release in 2021, hopes to unveil newer prediction methods and indicate faster warming than previously indicated, according to Robert DeConto, a glaciologist at the University of Massachusetts in Amherst. Meanwhile, Ted Schuur, a report author and permafrost ecologist at Northern Arizona University, has reminded us that “(whilst) the rapidity of change sometimes leads people to think it’s too late. . . it’s not.”
