Down To Earth Magazine – March, Optional Geography Current Affairs 2021
Topics Covered – Under-nutrition, Volcano In Reykjanes Peninsula, Expansion Of Mid-Atlantic Ridge, Laschamps, Temporary Reversal Of Magnetic Poles
Topic 1
Many sources of nutrition
This is with reference to “Rise in teenage pregnancies, poor maternal health hurdle to breaking intergenerational cycle of undernutrition” published online on February 3, 2021. The essence of milk is to serve as a source of nourishment until infants can digest solid food. In fact, milk has less calcium as against sesame seeds , spinach and other plant sources. So, the cruelty bestowed upon dairy animals while procuring milk is unnecessary and will not go unnoticed by the media and the public anymore.
THE FIRST two months of 2021 have been unusually hot for India, especially the northern parts of the country.
The warm weather is uncharacteristic given that 2021 began as a La Niña year. La Niña is the cooling phase of the El Niño Southern Oscillation cycle in the equatorial Pacific Ocean. It brings colder winters to India. However, the current La Niña conditions that began in October last year have only had a moderate cooling effect, probably because the impact of global warming has become more pronounced.
Topic 2
•Massive earthquakes alarm seismologists • •
A SWARM of nearly 20,000 earthquakes across Iceland since February 24 has worried scientists, who fear the heightened seismic activities could lead to a volcanic eruption in the Reykjanes Peninsula of the southwestern region of the country.
Topic 3
Slowly pulling apart the peninsula
After a series of major eruptions between the 10th and 13th centuries, the Reykjanes Peninsula been pretty calm. That changed at the end of 2019, when the peninsula started quaking more frequently and violently. A magnitude-5.7 quake in February of this year shook the region, and this week quakes were coming thick and fast.
Key to this tectonic bedlam is the fact that Iceland sits on the northern part of the Mid-Atlantic Ridge, a split in the seafloor that stretches down the length of the world. Here, lava erupts and cools to make a new oceanic crust on either side of the rift. The North American and Eurasian tectonic plates sit to the west and east of it, respectively, and they have pushed away from each other at roughly the same speed as your fingernails grow.
Most of the Mid-Atlantic Ridge is underwater, but the Reykjanes Peninsula sits on the northern part of the ridge, so it’s gradually being pulled apart all the time. For reasons unknown, once every 800 years or so, the rifting suddenly escalates, causing a major uptick in tectonic earthquakes, as is happening now. Ancient lava flows studied by geologists and historical accounts from Iceland’s early settlement note that when you get a serious spike in quakes here, magma follows.
Ronlau817, CC BY-SA 4.0 <https://creativecommons.org/licenses/by-sa/4.0>, via Wikimedia Commons
Topic 4
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