Environment & science roundup March 5 2024: Kochi weather, El Nino started melting Antarctica Doomsday glacier in the 1930s, red net protection for crops, upcoming total solar eclipse

Embracing sustainable agricultural practices and seeking alternatives to chemical pesticides is crucial for the future of farming. (Photo credit: Christian Heitz via Pexels)

1. El Niño spurred melting of Antarctica’s 'Doomsday Glacier': An extreme El Niño event triggered the melting of Antartica's so-called Doomsday Glacier, Thwaites, in the 1940s. The glacier is as big as Florida, and if it melts completely, sea level could rise by as much as 60 cm - this in turn could trigger large-scale destruction, especially in coastal areas.

Scientists had originally pegged 1980s as the time when the glacier on Antarctica started melting rapidly, contributing to a 4 percent rise in global sea levels by losing around 595 billion tonnes of ice.

The new study was led by Rachel Clark from the University of Houston, Texas, and used sediment cores from seven locations near the Thwaites and its northern neighbour, the Pine Island glacier, to trace their retreat.

2. 35 percent of Kochi vulnerable to heat stress, 25 percent to flooding: A recent study by the World Resources Institute (WRI), India, found that roughly 35 percent of Kochi’s residents are vulnerable to heat stress, and 25 percent face risks of flooding.

Kochi is a coastal city with dense population and limited adaptive capacity - 47 percent of Kochi’s land area lies within floodplains and 26 percent of its population lives there. The WRI report also highlighted the threat of urban inundation during heavy rainfall events.

Unplanned urbanisation in recent decades has made the city even more susceptible to climate hazards - especially sea level rise and coastal erosion, both of which could impact critical infrastructure such as ports, airports, railways, and the metro.

3. Switching to red nets keeps pests away and protects crops, finds new study: At a time when sustainable agriculture has become a buzzword and efforts are on to reduce farmers' reliance on pesticides, researchers at Japan's Tokyo University have tested an "optical pest control" method: the use of red nets!

This pest control method uses our knowledge of insect colour vision and behavioural responses, for more sustainable crop protection solutions.

The study found that when used to shield crops, red nets could reduce pest invasion and damage such as white spots on the leaves caused by onion thrips—the main vector of the Iris Yellow Spot Virus and the Tomato Spotted Wilt Virus. The research was conducted in both a lab and a Welsh onion greenhouse with minimum use of pesticides.

That red mesh is a one-time expenditure means it should work out to be cheaper for farmers compared with pesticide use. Additionally, red mesh was found to work even when the mesh holes were large - allowing sunlight to come through and protect crops against fungal damage too.

Of course, the idea will have to be tested in other geographies, and for more crops. But it is a move in the right direction, given all that we know about the effects of chemical pesticides on our health and the health of the planet.

4. How ancient cultures explained a solar eclipse: The 2024 total solar eclipse on April 8 is just over a month away. It will be properly visible in the US and Mexico, but of course cultures all over the world have their beliefs around solar eclipses. Here's how some ancient cultures explained solar eclipses:

a. According to ancient Chinese mythology, solar eclipse occurs when celestial dragons attack and eat the sun.

b. Solar eclipses are linked to Rahu in Hindu mythology. The legend goes that Rahu sought immortality by drinking the nectar of the gods. When Vishnu beheaded him, Rahu's head flew across the sky - and it sometimes swallows the sun as it travels the skies.

c. According to American Indian Choctaw legend, a black squirrel causes eclipses by nibbling away at the sun.