Category Science

What is El Nino climate pattern?

This affects ocean temperatures, speed and strength of ocean currents, the health of coastal fisheries, and also the local weather in several countries

The World Meteorological Organisation (WMO) has predicted a high probability of El Nino developing later this year. This will fuel higher global temperatures. Let us know more about this phenomenon.

El Nino

El Nino, Spanish word for ‘little boy’, is a natural climate pattern associated with the warming of the central Pacific Ocean waters near South America. It is the warm phase of El Nino-Southern Oscillation (ENSO), a recurring phenomenon involving changes in the Pacific Ocean temperature.

El Nino affects the ocean temperatures, speed and strength of ocean currents, the health of coastal fisheries, and also the local weather in several countries. For instance, El Nino can cause rain in South America while threatening drought in Indonesia and Australia.

It occurs irregularly at two- to seven-year intervals and episodes usually last nine to 12 months. An El Nino year creates a mini global-warming crisis because the warm water spreading across the tropical Pacific releases a large amount of heat into the atmosphere. It results in hot and dry weather in Southeast Asia.

El Nino events are indicated when the temperature of the sea surface increases by more than 0.5° C for at least five successive overlapping three-month seasons.

El Nino events of 1982-83 and 1997-98 were the most adverse of the 20th Century. During 1982-1983, the sea surface temperatures in the eastern tropical Pacific were 7.8-12.8° C above normal. These strong temperature increases caused harsh drought in Australia, typhoons in Tahiti, and record rainfall and flood in central Chile.

The 1997-1998 El Nino event was the first time that was scientifically monitored from beginning to end. It caused drought conditions in Indonesia, Malaysia, and the Philippines. Peru faced very heavy rains and severe flooding. While California faced winter rainfall, the Midwest received record-breaking warm temperatures. Strong El Nino events can cause weaker monsoons in India and Southeast Asia and increased rainfall during the rainy season in sub-Saharan Africa.

ENSO and La Nina

ENSO involves changes in the temperature of the central and eastern tropical Pacific Ocean. This affects the rainfall distribution in the tropics and weather across the world. El Nino and La Nina are the extreme phases of the ENSO cycle. Besides, there is another phase neither El Nino or La Nina. It is known as the ENSO-neutral.

La Nina, Spanish word for ‘little girl’, is the cool phase of ENSO. During La Nina events, trade winds (blowing east to west just north and south of the Equator) are stronger than usual and push more warm water toward Asia. Meanwhile, near the west coast of the Americas, upwelling increases, bringing cold and nutrient-rich water to the surface. During such a year, the winter temperatures are warmer than normal in the South and cooler than normal in the North. La Nina ended this year after a three-year run and the tropical Pacific is at present in an ENSO-neutral state.

Prediction

The WMO has predicted a 60% chance for a transition from ENSO-neutral to El Nino during May-July 2023, an increase to about 70% in June-August and 80% in July-September.

This April, the India Meteorological Department (IMD) predicted that an El Nino will likely develop during this southwest monsoon. However, the IMD has stated that India will likely receive a normal amount of monsoon rain this year despite the probability of the weather phenomenon.

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Scientists have achieved the world’s first X-ray signal (or signature) of just one atom

From medical examinations and airport screenings to space missions, X-rays have been used everywhere since its discovery by German physicist Wilhelm Roentgen in 1895. A group of scientists from Ohio University, Argonne National Laboratory, the University of Illinois-Chicago, and others, have now taken the world's first X-ray signal (or signature) of a single atom. The groundbreaking achievement could revolutionise the way in which scientists detect the materials.

One atom at a time

Before this, the smallest amount one can X-ray a sample is an attogram, which is about 10,000 atoms or more. The paper brought out by the scientists was published in the scientific journal Nature on May 31, 2023 and also made it to the cover of the print edition on June 1. The paper details how physicists and chemists used a purpose-built synchrotron X-ray instrument at the XTIP beamline of Advanced Photon Source and the Center for Nanoscale Materials at Argonne National Laboratory.

Specialised detector

The team involved picked an iron atom and terbium atom for their demonstration. Both atoms were inserted in respective molecular hosts. Conventional detectors were supplemented with a specialised detector by the research team.

This specialised detector was made of a sharp metal tip. It is positioned at extreme proximity to the sample, enabling it to collect X-ray excited electrons. This technique is known as synchrotron X-ray scanning tunnelling microscopy or SX-STM.

Apart from achieving the X-ray signature of an atom, the team also succeeded in another key goal. This was to employ their technique to find out the environmental effect of a single rare-earth atom.

The scientists were able to detect the chemical states of the individual atoms inside respective molecular hosts and compare them. While the terbium atom, a rare-earth metal, remained rather isolated and didn't change its chemical state, the iron atom interacted with its surrounding strongly.

Many rare-earth materials are used in everyday devices like cell phones, televisions, and computers. This discovery allows scientists to not only identify the type of element, but also its chemical state. Knowing this enables them to work on these materials inside different hosts, paving the way for further advancement of technology.

This team aims to continue to use X-ray to detect properties of a single atom. They are also seeking ways to revolutionise their applications so that they can be put to use in critical materials research.

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What are solar trees and solar canopies?

Solar trees and solar canopies are all about the idea of taking solar energy to another level. Solar energy is a renewable source of energy. It is cheaper, perennial, and environmentally friendly.

Tapping into solar energy is a revolutionary way to drive renewable energy production and reduce our dependence on fossil fuels which release harmful greenhouse gases and thereby lowers our carbon footprint.

And to promote the use of solar energy, sustainable, aesthetic-looking solar structures such as solar trees and solar canopies have come up. Here we harness the energy of the sun to generate electricity.

Ever seen the Supertrees in Singapore? Remember those colossal structures that look like trees right out of a science fiction novel. Those are solar trees.

A collection of 18 artificial Supertrees ranging in height upto 50 metres, were set up in Singapore at “Gardens by the Bay” (a botanical project). These solar trees also serve as vertical gardens with ferns and vines climbing up the steel framework.

So what are solar trees? A solar tree is a structure resembling a tree and generating solar energy using photovoltaic (PV) panels.

How does a solar tree work?

 In a solar tree, the photovoltaic “leaves” will capture the sunlight and convert it into electricity. This is then conducted down through the framework that resembles the trunk of a tree to an internal battery.

Some designs of solar trees feature rotating panels and these can move throughout the day and absorb more amounts of sunlight.

These are futuristic “trees” and can be set up even in rural communities or other off-grid locations. They can be used to supplement other methods of harnessing sunlight.

Why solar trees?

One of the main perks of setting up solar trees is that they help save land as they are vertical. Due to their towering height, they can also receive more sunlight than solar panels mounted on a lower ground.

If you were to take a look at the Supertrees in Singapore, you can see that the steel framework is covered by climbers and floral species, increasing the aesthetic value. Thus it also adds to the biodiversity of the urban locale. Moreover, these trees require less maintenance compared to other means of solar energy production. They also help cool the heat islands by reducing the thermal energy that gets reflected off surfaces. These structures can thus help offset the effect of climate change.

Solar canopy

Now what are solar canopies? A solar canopy is a structure that is designed to cover an outdoor area. They are rooftops that are used to harness solar energy using photovoltaic panels.

They also provide shelter in expansive areas. One can even say that the future of parking lies in solar canopies. They are slowly becoming popular in public places and businesses. These green roofs are mostly used as transportation infrastructure (bus shelters, or parking lots) or in recreational areas.

Solar canopies help in decentralised energy production and have an edge over huge grid-based power systems as these can help avoid grid failures and power outages. Despite their advantages the solar canopies are not that common. This is expected to change over time.

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How soil came to be?

Soil is almost everywhere around us that we don’t give it much thought. But it is so crucial that life as we know it will cease to exist without soil. Here’s a peek into how soil came to be.

Though Earth is over 4.5 billion years old, the soil it holds is less than 500 million years old. Before soil came about, the continents of our planet were “dusty, barren and rocky landscapes similar to the surface of Mars”. All that dramatically changed with the birth of soil. It was earlier believed that rivers weathering bare rock resulted in soil, but more recent research suggests that land plants are largely responsible for the formation of soil.

Freshwater algae gradually evolved to become land plants, which quickly gained complex forms. So quickly that 385 million years ago, there were forests the world over. These forests “sucked carbon dioxide out of the atmosphere at a rapid rate”. This resulted in global temperatures falling and causing widespread glaciations. These “helped to grind down Earth’s rocks”. But there was also something else at play – roots.

There’s evidence that early plant roots were not the way they look today. There were just thin stems covered in tiny hairs, which helped “anchor plants to the planet’s rocky surface and absorb water and nutrients”. The new hairy stems intertwined with decaying older stems to result in a thin-layered peaty soil enough to offer a foothold for more plants to grow. In about 20 million years, plant roots evolved and “drilled down over a metre in depth”, transforming soils and letting plants gain access to deep reserves of water and nutrients. “This below-ground revolution provided an entirely new ecosystem for life to diversify into.” From fungi and mites to roundworms and early arachnids, the soil was just bursting with life. Meanwhile, the penetration of roots into the ground also helped broad sheets of water on land to flow deeper to become what we now call rivers. It is said plant roots may have evolved further since then, impacting soil.

Given how important soil is for water, nutrients, and absorbing carbon, it is worrying that globally our soil is in peril due to several factors, including erosion. And this is a reminder that we must protect it.

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What is meaning of term ‘Painting with words’?

The technical advancement in Artificial intelligence or Al has helped recognise CT scans for doctors, predict oil deposits for engineers, and create and regulate algorithms among other things. But can Al generate art?

Creating art takes a unique combination of skills, creativity and the very human element of aesthetic taste. In April 2022, OpenAl, an artificial intelligence (AI) research laboratory, came up with a text-to-image generator that can draw anything you want virtually. This has been done before but the difference here is that the fleshed-out painting or images created by this system replicated the aesthetic design and taste of a real artist. This new Al system is called Dall-E 2 and is capable of turning any text description into a unique work of art. This is an updated system of Dall-E which was released by the company last year. The high-quality and high-resolution images generated by Dall- E 2 are completed within 10 seconds after one enters the prompts and also feature complex backgrounds, realistic depth, and shadow effects, shading and reflections. This free-for-all Al-powered software has made art more accessible, giving everyone a platform to create pictures with words without having to actually execute them with paint, cameras, or code.

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What is meaning of term ‘Blockchain, NFT’?

Blockchain and NFT are buzz words in the technology industry today.

Blockchain corresponds to a distributed database that maintains a continuously growing list of ordered records, called blocks. These blocks are then linked using cryptography. A blockchain thus serves as a decentralised distributed and public ledger that is used to record transactions across many computers.

NFT stands for non-fungible token. As it is non-fungible, it cannot be replaced or exchanged for something of identical value. Basically blockchain tokens representing unique digital items. NFT allows you to buy and sell ownership of unique digital items.

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