06/10/2017 UPSC PRELIMS 2018 DAILY CURRENT AFFAIRS




‘Spate of hurricanes reminder of urgent action on climate change’

Finding : Scientists say there are links between climate change and extreme weather- UN chief - this year’s Atlantic hurricane season “will be the new normal of a warming world.”


The new normal :

  • Hurricane Irma in Barbuda - Category 5 storm for 3 days - the longest on satellite record”, and its winds - 300 kmph for 37 hour - the longest on record at that intensity.”

  • Hurricanes Harvey and Irma - first time two Category 4 storms and land fall

  • Hurricane Maria - Category 5 storm in Dominica and devastating Puerto Rico.


Indications for extreme weather changes:

  • A warmer climate -turbocharges the intensity of hurricanes.

  • The melting of glaciers, and the thermal expansion of the seas, means bigger storm surges

Result of extreme weather : More damages to coastal area


Major climatic changes :

  • Sea levels have risen more than 10 inches since 1870 and over the last 30 years

  • The number of annual weather-related disasters has nearly tripled

FACTS FOR PRELIMS

  • UN Chief : Secretary-General Antonio Guterres

  • World Bank and Antigua government have conducted a post-disaster needs assessment for Barbuda

  • Eastern Caribbean islands hardest hit by recent hurricanes are Dominica, Barbuda, Turks andCaicos, the British Virgin Islands and Anguilla,


RELATED NEWS EVENT : Here’s how lava-spewing mountains affect climate - Volcanic eruptions can trigger El Nino events, according to study


WHAT HAPPENS > Large volcanic eruptions in the tropics can lead to El Nino events, notorious warming periods in the Pacific Ocean with dramatic global impact on the climate- a new study.


HOW > Published in journal Nature Communications .

STAGE 1 : Enormous eruptions trigger pump millions of tonnes of sulfur dioxide into the stratosphere

STAGE 2 : Which form a sulfuric acid cloud

STAGE 3:This reflect solar radiation and reduce the average global surface temperature


Method to study after effects of eruption : How much sulfur dioxide goes into the stratosphere — and you can measure it with satellites the day after an eruption


PAST EXPERIENCE : El Nino peak during the year after large volcanic eruptions at Mount Pinatubo in the Philippines in 1991.


Five big eruptions — Santa Maria (Guatemala) in October 1902, Mount Agung (Indonesia) in March 1963, El Chichon (Mexico) in April 1982 and Pinatubo in June 1991.


THE MAJOR ONE : The study focussed on the Mount Pinatubo eruption because it is the largest and best-documented tropical one in the modern technology period. It ejected about 20 million tonnes of sulfur dioxide.


Findings : Pinatubo-like eruptions tend to shorten La Ninas, lengthen El Ninos, and lead to unusual warming during neutral periods.


FACTS FOR PRELIMS :

  • THE ENSO : The El Nino Southern Oscillation (ENSO) is Nature’s leading mode of periodic climate variability. It features sea surface temperature anomalies in the central and eastern Pacific.

  • THE El Nino Cycle : ENSO events (consisting of El Nino or La Nina, a cooling period) unfold every three to seven years and usually peak at the end of the calendar year, causing worldwide impact on the climate by altering atmospheric circulation


CLICK HERE FOR PART II - FOR POLITY, SCI-TECH, ENVIRONMENT

Courses Offered

Recent Post

Achievements