Question: Jakobshavn Isbrae glacier is located at –
a) Alaska
b) Greenland
c) Denmark
d) Antarctica
Answer: (b)
Related Facts:
- In a new study it has been found that the three largest glaciers of Greenland are melting at a faster rate than previously expected.
- Together, the three glaciers hold enough ice to increase the global sea level by at least 1.3 metres if melted.
- The study was published in the journal Nature on, 17 November 2020.
- Researchers say that such an extent of sea-level rise could inundate several major coastal cities like Mumbai and Chennai.
- In their study, researchers examined three largest glaciers of Greenland in particular, namely Jakobshavn Isbrae, Kangerlussuaq Glacier and Helheim Glaciers.
- The team used various sets of data derived from historical photographs, recent satellite images.
- Researchers also used aerial stereo-photogrammetric imagery to calculate the ice loss between the time span 1880–2012.
- After studying various datasets, the team found, Jakobshavn Isbrae—situated in west Greenland—lost a total of 1.5 trillion tonnes of ice in the past 132 years.
- Kangerlussuaq—situated on the east coast—lost 1.4 trillion tonnes of ice chunk in-between years 1900-2012.
- Helheim glacier has lost 31 billion tonnes of ice in the same period.
- Combined, the ice melt from these three sources has already contributed to the rise of sea levels by 8 mm.
- The Greenland Ice Sheet is the largest land ice contributor to sea-level rise.
- This will continue in the future but at an uncertain rate and observational estimates are limited to the last few decades.
- The study project that the future sea-level rise from these glaciers can be noted at 9.1–14.9 mm by 2100.
- The study is based on the scenario named Representative Concentration Pathways Model or RCP 8.5.
- The research paper explained that RCP 8.5 implies an additional global temperature increase of 3.7 °C by 2100, approximately four times larger than that which has taken place since 1880.”
- The impact of sea-level rise can be severe as it can impact the lives of nearly 287 million people due to flooding.
- Moreover, the United Nations scientific body, the IPCC, projects that the global sea-level rise could be between 30-110 centimeters by 2100.
- As per the study, until 2000, the main reason for the sea-level rise was attributed to melting glaciers and the expansion of the ocean water.
- But over the last two decades, the ice sheets which largely cover Greenland and Antarctica have become another source of global sea-level rise.
By – Rajesh Tripathi