Current Affairs

Issue

A report by the Intergovernmental Panel on Climate Change (IPCC) has warned that by 2100 the average global temperatures would breach the two degrees Celsius.

 

Background

A study of global temperature rise that occurred 56 million years ago was conducted by a research team.

 

Details

• The study showed that the climate stabilized after 20,000 to 50,000 years after a rise of five to eight degrees Celsius. 

• A natural period of global warming known as the Paleocene-Eocene Thermal Maximum (PETM) was witnessed by Earth many years ago.

• Huge amounts of carbon dioxide were released into the atmosphere triggered by a volcanic eruption event.

• Ocean surfaces in higher latitudes saw their temperature increase by 8 degree Celsius. This acidification caused mass extinctions in the deep ocean.

 

The study

• The team analyzed rocks, single-celled marine organisms, clay minerals, and lithium isotopes to identify changes that took place.

• The global warming event resulted in erosion of rocks. These eroded rocks released lithium in water bodies. By studying the lithium isotopes, erosion levels can be understood.

• Lithium is not used by plants or biology. The amount of lithium that is released can only come from erosion process.

• They also studied single-celled organisms with calcareous shells known as planktonic foraminifera, which lived millions of years ago.

 

Consequences

• The PETM had high rise in temperatures but was slow. The current rise is restricted to only 3-4 degree Celsius but is very quick.

• The recovery period will probably be broadly similar in timing. The findings will only hold if there is significant reduction in CO2 emissions.

 

Solutions

Scientists are looking at a way known as ‘enhanced weathering’ which involves grinding up rock into powder and ploughing it into fields, where it can remove CO2 and act as a fertilizer.