CYCLONE TAUKTAE: LINK WITH CLIMATE CHANGE

The country is witnessing this year’s maiden cyclonic storm named ‘Cyclone Tauktae’ in the Arabian Sea, with a sustained wind speed of 135-145 gusting to 160. The storm has intensified rapidly, strengthening into a severe cyclonic storm in a span of 24 hours.

The cyclone is presently seen over the East-central Arabian Sea, running parallel to the West Coast around 220 km South-southwest of Panjim, 590 km south-southwest of Mumbai and 820 km south- southeast of Veraval.

Weather conditions are very much favourable for the further intensification of Tauktae into a very severe cyclonic storm in the next 12 hours. Sea surface temperatures and atmospheric conditions indicate that it may even gather further strength. During this time, Tauktae is likely to induce high-velocity winds to the tune of 150-160 kmph gusting up to 170 kmph.

Moving in the north-northwest direction, Tauktae is likely to make landfall around May 18 over the Gujarat coast between Porbandar and Naliya with a sustained wind speed of 145-155 Kmph gusting up to 170 Kmph. CYCLONE TAUKTAE: LINK WITH CLIMATE CHANGE 0 2

According to Mahesh Palawat, meteorologist at Skymet Weather, “The eye of the storm clearly indicates that the cyclone is well- marked. Moreover, with long sea travel ahead that too with warm SSTs, Tauktae would gain more strength.” CYCLONE TAUKTAE: LINK WITH CLIMATE CHANGE 0 3

Tauktae would continue to pound widespread heavy rains accompanied by torrential winds along the entire west coast during the next 24-48 hours. As the system moves northwards, the rains would reduce in the southern parts.

Sea conditions are already rough to very rough. In wake of this, fishermen and locals are advised against venturing out in the sea for the next 48-72hours.

Climate change is increasing the damage that cyclones like Tauktae cause in several ways, including:

A steep increase in sea surface temperatures (SST) intensifies the storm significantly. Usually, the SST in the Arabian Sea is around 28°C-29°C, which at present are around 31°C Increasing the rainfall that drops during the storm Rising sea levels, which increases the distance inland that storm surges reach, Causing storms to gain strength more quickly

With this, cyclone Tauktae develops over the Arabian Sea, it is now clear that India will see more frequent cyclones every year due to global warming.

Cyclonic storms are considered to be the most devastating extreme weather events that India faces every year. The strong winds and heavy rains that accompany cyclones cause immense loss of life and property along the coastline of India.

Temperature and storm strength

Cyclones are fueled by available heat in the water bodies. The conducive temperature for the intensification of the cyclone is 28°C and above. The Bay of Bengal is usually warmer than the Arabian Sea and thus, hosts more tropical storms. However, the scenario is now changing as we have seen SST temperatures increasing rapidly in the last century. CYCLONE TAUKTAE: LINK WITH CLIMATE CHANGE 0 4

As a result, SSTs in the Arabian Sea are over the threshold values. These warmer temperatures are directly indicative of active convection, torrential rainfall, and intense cyclones. The same has been witnessed during the last 48 hours wherein Kerala has reported widespread 3-digit rainfall at many places, resulting in a flood-like situation.

Globally, ocean temperatures have increased as a result of climate change - and there has been a global increase in the observed intensity of the strongest storms over recent decades. Cyclone Tauktae has confirmed this trend, finding that the proportion of the strongest storms is increasing about 8% a decade.

These higher sea-surface temperatures increased the energy available to the storm: CYCLONE TAUKTAE: LINK WITH CLIMATE CHANGE 0 5

Rapid intensification

Cyclones are now intensifying rapidly owing to warm ocean waters. Recent cyclones like Ockhi, Fani, and Amphan have confirmed the trend as they have intensified from a weak cyclonic storm to an extremely severe cyclone in less than 24 hours due to exceptionally warm SSTs.

Rapid intensification is expected to continue to become much more frequent this century with continued climate change. One study found that intensification rates that happen once a century now could happen every 5-10 years by 2100.

This kind of rapid intensification has posed serious challenges to forecasting capacity. Officials are unable to give a quick response as they are not able to judge the ocean dynamics accurately. Thus, we need to change the way of thinking as well as gauging the situation accordingly.

Experts quotes

Dr Roxy Mathew Koll, Scientist, Indian Institute of Tropical Meteorology, Lead Author, IPCC Oceans and Cryosphere

With Cyclone Tauktae, this will be the fourth consecutive year of pre-Monsoon cyclone over the Arabian Sea. This is also the third consecutive year when a cyclone has come very close to the west coast of India. Sea Surface Temperatures in the Arabian Sea have increased rapidly during the past century and this has led to an increase in the frequency and intensity of cyclones in the Arabian Sea.

Efficient forecasts require efficient monitoring of the ocean, but we have gaps there too. We can monitor and track these cyclonic systems through the buoys and instruments in the oceans, satellites in the sky, and weather models running on high-performance computers. CYCLONE TAUKTAE: LINK WITH CLIMATE CHANGE 0 6

Global warming has presented us with new challenges such as rapid intensification of cyclones, which need to be closely monitored at higher resolution and accuracy using on-site platforms such as buoys and moorings. Improving the Indian Ocean Observing System (IndOOS) and incorporating the global warming signals in the weather models can help us tackle the challenges of intense cyclones in the future.

Climate projections indicate that the Arabian Sea will continue warming due to increasing carbon emissions, resulting in more intense cyclones in the future. Considering that both cyclones and floods due to heavy rains are increasing across the west coast along with a gradual rise in sea level, we need to be prepared.

With the data that we have collected, and our weather and climate models, it is possible to understand how the cyclones might change in the coming decades and how that might impact the coastline of India. A risk assessment based on this can definitely help save lives and property.

Dr Anjal Prakash, Research Director and Adjunct Associate Professor, Bharti Institute of Public Policy, Indian School of Business. Lead Author, IPCC’s AR6 and Coordinating Lead Author, IPCC Oceans and Cryosphere report

The cyclone Tauktae is likely to intensify as a severe cyclone in the next couple of hours. The disturbing part of this development is the frequent occurrence of pre-monsoon cyclones in the Arabian sea. The past couple of years have seen a surge in the occurrence and severity of these cyclones which were a rare phenomenon earlier.

As part of IPCC’s special report on Oceans and the Cryosphere, I had experienced these discussions amongst scientists whose predictions are coming true. Due to climate change, globally, our oceans have warmed up to 0.8-degree centigrade from the pre- industrial age. CYCLONE TAUKTAE: LINK WITH CLIMATE CHANGE 0 7

The Arabian sea has warmed up to 1.2 to 1.4 degree C in recent years. The Arabian sea has sunk the carbons we have emitted into the atmosphere leading it to be warmer and more acidic.

The warm oceans feed into cyclone systems that have devastating impacts on the life people in the coastal areas. India has one of the longest coastlines of 7500 km and therefore our vulnerabilities to the cyclones are exposed every time a new cyclone makes a landfill. So, what could be done to adapt to these increased occurrences which could be attributed to climatic events?

I would like to focus on three areas – first, our coastal infrastructure needs to be climate-resilient. The present infrastructure is not tuned into catering to extreme events. Second, our response has always been knee-jerk. We need a special task force to tackle these in the longer term and scientists, as well as people working on adaptation, must be part of this process that informs the government and share their views which can influence policies and programmes. The science-policy dialogue is suggested via a formal network. Third, community institutions especially panchayats and local level administrative bodies in coastal districts must come together as a unit. They need to be incapacitated to take actions via community groups for rescue, rehabilitation, and adaptation.

This cyclone has come when we are already fighting the second wave of COVID. It is indeed a double whammy and the only way we can deal with this in long term is via strengthening institutions and people in the process.