• This field is for validation purposes and should be left unchanged.
home_icon-01_outline
star
  • Earth.Org Newsletters

    Get focused newsletters especially designed to be concise and easy to digest

  • This field is for validation purposes and should be left unchanged.
Earth.Org PAST · PRESENT · FUTURE
SHOP Support

A study has found that tropical cyclones have become wetter, more destructive and more frequent in the past four decades, with more intense storms forming as a result of warming ocean temperatures. 

Published in the journal Proceedings of the National Academy of Sciences, researchers analysed satellite records from 1979 to 2017 and found a rise in the cyclones that have winds of about 185 km/h. Scientists carried out the study at the US government’s National Oceanic and Atmospheric Administration (NOAA).

How does climate change affect typhoons?

The researchers found that the likelihood of a storm reaching Category 3 or above, with sustained winds of 185km/h, increased by 8% per decade. James Kossin, author of the study, says, “In other words, during its lifetime, a hurricane is 8% more likely to be a major hurricane in this decade compared to the last decade.”

The study found that as well as increasing wind speeds in cyclones, warming oceans would also likely see more rainfall from cyclones. Previous research shows that when cyclones form, they are tending to move more slowly, while delivering more rain. However, there is uncertainty as to whether the numbers of all categories of cyclones would rise or fall under the climate crisis.

You might also like: The Arctic Will Have Ice-Free Summers by Mid-Century, Escalating Sea-Level Rise

Additionally, the study looked at changes in cyclone intensity by region and found that trends toward stronger storms are clearest in the north Atlantic, southern Indian and eastern north Pacific oceans. 

According to experts speaking to Guardian Australia, the findings are in line with climate model predictions and the knowledge that increasing ocean temperatures give tropical cyclones more energy. 

Dr Greg Holland, a scientist at the National Centre for Atmospheric Research, says, “There is nobody saying the trend will go the other way. The physics has been well set out for 30 or 40 years. If you get a warmer ocean, then the intensity of cyclones goes up. That’s a 5% or 10% increase in maximum winds for every 1°C of warming in the ocean. The world is warming and it’s because we have put more greenhouse gases into the atmosphere.

Dr Holland also suggests that storms are moving further away from the equator, but acknowledges that this is harder to confirm observationally. 

Increasingly destructive tropical cyclones will cause more damage to coastal communities, which are already at an increased risk of being affected by the climate crisis due to sea-level rise. 

The ocean absorbs vast quantities of heat as a result of increased concentrations of greenhouse gases in the atmosphere. According to the IPCC’s Fifth Assessment Report in 2013, the ocean had absorbed more than 93% of the excess heat from greenhouse gas emissions since the 1970s, causing ocean temperatures to rise. Data from the NOAA shows that the average global sea surface temperature has increased by 0.13°C per decade over the past century. The IPCC’s report predicts that there is likely to be an increase in mean global ocean temperature of 1-4°C by 2100.

With many rivers dwindling and the groundwater in India nearly exhausted, an acute water scarcity crisis is underway in the world’s second-most populous nation.

Causes of Water Scarcity in India

Taps have run dry in India as millions of people brace themselves for the dreaded blend of extreme heat and water shortages during the summer. A combination of climate change, inefficient water use, and inadequate infrastructure has thrown India into a full-blown water scarcity crisis, forcing the government to create a brand new ministry–‘Jal Shakti Ministry’–to tackle the issue.

Water Scarcity in India: Statistics

This year, more than 330 million people are affected due to water scarcity as half of the nation’s land area grapples with drought-like conditions. 12% of the population, majority of them living in metropolitan cities like Bengaluru, Chennai, Delhi, and Hyderabad, are already facing the ‘Day Zero’ scenario, wherein most of their water supplies came to a complete halt. As many as 21 major cities including the national capital–New Delhi–is poised to run out of groundwater next year, according to a report by government-run think tank NITI Aayog. 

By definition, India now is a water-stressed country, where annual per capita water availability is below 1500 cubic metres. Half a century ago, it was 5200 cubic metres.

An assessment by the government indicates that the nation is gradually inching towards a calamity with the annual per capita availability likely to drop below 1000 cubic metres.

Climate change has pushed India’s climate towards extremes disrupting the quantity and frequency of rainfall. The country witnessed below average monsoon for the last two consecutive years. The North-East monsoon which provides 10-20% of India’s rainfall was deficient by 44% in 2018 as per data from the India Meteorological Department (IMD). This compounded the rainfall deficit in the South-West monsoon that provides 80% of the country’s rainfall, which fell short by 10% last year. Lower rainfall has reduced water levels in reservoirs across the country. During the first half of this year, 91 major reservoirs recorded 32% drop in their water capacity.      

Chennai, a coastal city of 10 million, had 55% less rainfall this year. The city went without rain for 200 days with its four water reservoirs turning into puddles of cracked mud causing the worst water scarcity crisis in 70 years.

You might also like: Earth Had its Second-Warmest March Ever

Puzhal reservoir in Chennai, India, has been reduced to a dry lake bed in just one year.

Unusual temperatures caused by climate change have made rainfall erratic with significant changes in monsoon patterns making droughts and floods more common in many parts of India. In 2015, a massive flood, spurred by unusually massive rainfall, devastated Chennai killing more than 500 people and leaving the city ravaged. Last year, flash floods in the states of Kerala and Karnataka caused distress while cyclones wreaked havoc in Tamil Nadu and Odisha.

India is rated ‘high risk’ in the Climate Change Vulnerability Index with major Indian cities are projected to experience a higher number of consecutive drought days with less rainfall in the near future. Changes in temperature, precipitation, and humidity will significantly impact the quality and quantity of water across the country, where water resources are also under unprecedented pressure from population growth, rapid urbanisation, and inefficient water use.

The water scarcity crisis is not unique to India. Globally, over 880 million people–about one in every nine people in the world–do not have access to clean water within 6 km of their homes. The United States Agency for International Development (USAID) predicts that approximately one-third of the world population will face chronic water crisis by 2025.

Freshwater constitutes only 2.5% of the total water on our planet and much of it is trapped in icecaps and glaciers, making it inaccessible for us. In reality, a meagre 0.007% of the planet’s total water is available to feed its 7.7 billion people.

India Water Crisis: Solutions

To avoid the impending water crisis, India and other vulnerable countries need effective climate change adaptation strategies that reflect the importance of water management in reducing vulnerability and building climate resilience. It is also necessary to bring in technology to help harness water more efficiently and build long-term water conservation plans.

You might also like: 5 Biggest Environmental Issues in India in 2022

Subscribe to our newsletter

Hand-picked stories once a fortnight. We promise, no spam!

SUBSCRIBE
Instagram @earthorg Follow Us