|Extremely severe cyclonic storm (IMD scale)|
|Category 4 tropical cyclone (SSHWS)|
|Formed||November 3, 1970|
|Dissipated||November 13, 1970|
|Highest winds|| 3-minute sustained:185 km/h (115 mph)|
1-minute sustained:240 km/h (150 mph)
|Lowest pressure||960 hPa (mbar); 28.35 inHg|
|Fatalities||≥ 500,000 total|
(Deadliest tropical cyclone on record)
|Damage||$86.4 million (1970 USD)|
|Areas affected||India, East Pakistan|
|Part of the 1970 North Indian Ocean cyclone season|
The 1970 Bhola cyclone was a devastating tropical cyclone that struck East Pakistan and India's West Bengal on November 3, 1970. It remains the deadliest tropical cyclone ever recorded and one of the deadliest natural disasters. At least 500,000 people lost their lives in the storm,primarily as a result of the storm surge that flooded much of the low-lying islands of the Ganges Delta. This cyclone was the sixth cyclonic storm of the 1970 North Indian Ocean cyclone season, and also the season's strongest.
A tropical cyclone is a rapidly rotating storm system characterized by a low-pressure center, a closed low-level atmospheric circulation, strong winds, and a spiral arrangement of thunderstorms that produce heavy rain. Depending on its location and strength, a tropical cyclone is referred to by different names, including hurricane, typhoon, tropical storm, cyclonic storm, tropical depression, and simply cyclone. A hurricane is a tropical cyclone that occurs in the Atlantic Ocean and northeastern Pacific Ocean, and a typhoon occurs in the northwestern Pacific Ocean; in the south Pacific or Indian Ocean, comparable storms are referred to simply as "tropical cyclones" or "severe cyclonic storms".
East Pakistan was the eastern provincial wing of Pakistan between 1955 and 1971, covering the territory of the modern country Bangladesh. Its land borders were with India and Myanmar, with a coastline on the Bay of Bengal.
India, also known as the Republic of India, is a country in South Asia. It is the seventh largest country by area and with more than 1.3 billion people, it is the second most populous country as well as the most populous democracy in the world. Bounded by the Indian Ocean on the south, the Arabian Sea on the southwest, and the Bay of Bengal on the southeast, it shares land borders with Pakistan to the west; China, Nepal, and Bhutan to the northeast; and Bangladesh and Myanmar to the east. In the Indian Ocean, India is in the vicinity of Sri Lanka and the Maldives, while its Andaman and Nicobar Islands share a maritime border with Thailand and Indonesia.
The cyclone formed over the central Bay of Bengal on November 8, and traveled northward, intensifying as it did so. It reached its peak with winds of 185 km/h (115 mph) on November 11, and made landfall on the coast of East Pakistan (now Bangladesh) the following afternoon. The storm surge devastated many of the offshore islands, wiping out villages and destroying crops throughout the region. In the most severely affected Upazila, Tazumuddin, over 45% of the population of 167,000 was killed by the storm.
The Bay of Bengal is the northeastern part of the Indian Ocean, bounded on the west and northwest by India, on the north by Bangladesh, and on the east by Myanmar and the Andaman Islands of India and Myanmar and the Nicobar Islands of India. Its southern limit is a line between Sri Lanka and the northwesternmost point of Sumatra (Indonesia). It is the largest water region called a bay in the world. There are countries dependent on the Bay of Bengal in South Asia and Southeast Asia. The Bay of Bengal was also called the Chola Lake.
Upazila, formerly called thana, is an administrative region in Bangladesh. They function as sub-units of districts. Their functionality can be seen to be analogous to that of a county or a borough of Western countries.
Tazumuddin is an Upazila of Bhola District in the Division of Barisal, Bangladesh.
The Pakistani government, led by junta leader General Yahya Khan, was criticized for its delayed handling of the relief operations following the storm, both by local political leaders in East Pakistan and in the international media. During the election that took place a month later, the opposition Awami League gained a landslide victory in the province, and continuing unrest between East Pakistan and the central government triggered the Bangladesh Liberation War, which led to widespread atrocities and eventually concluded with the creation of the country of Bangladesh. This storm as well as the Bangladesh Liberation War and 1971 Bangladesh genocide and the subsequent refugees led ex-Beatle George Harrison and Bengali musician Ravi Shankar to organize The Concert for Bangladesh in 1971 in Madison Square Garden, New York City.
A military junta is a government led by a committee of military leaders. The term junta comes from Spanish and Portuguese and means committee, specifically a board of directors. Sometimes it becomes a military dictatorship, though the terms are not synonymous.
Agha Muhammad Yahya KhanNePl, widely known as Yahya Khan, was the third President of Pakistan, serving in this post from 25 March 1969 until turning over his presidency in December 1971.
The Bangladesh Awami League, often simply called the Awami League or AL, is one of the two major political parties of Bangladesh.
The remnants of Tropical Storm Nora from the West Pacific, which had lasted for two days in the South China Sea, moved west over the Malay Peninsula on November 5. N, 87° E, but began to accelerate toward the north on November 10.The remnants of this system contributed to the development of a new depression in the central Bay of Bengal on the morning of November 8. The depression intensified as it moved slowly northward, and the India Meteorological Department upgraded it to a cyclonic storm the next day. No country in the region had ever named tropical cyclones during this time, so no new identity was given. The storm became nearly stationary that evening near 14.5°
The South China Sea is a marginal sea that is part of the Pacific Ocean, encompassing an area from the Karimata and Malacca Straits to the Strait of Taiwan of around 3,500,000 square kilometres (1,400,000 sq mi). The sea carries tremendous strategic importance; one-third of the world's shipping passes through it, carrying over $3 trillion in trade each year, it contains lucrative fisheries, which are crucial for the food security of millions in Southeast Asia. Huge oil and gas reserves are believed to lie beneath its seabed.
The Malay Peninsula is a peninsula in Southeast Asia. The land mass runs approximately north-south and, at its terminus, is the southernmost point of the Asian mainland. The area contains Peninsular Malaysia, Southern Thailand, and the southernmost tip of Myanmar (Kawthaung) as well as the city state Singapore, indigenous to or historically inhabited by the Malays, an Austronesian people.
The India Meteorological Department (IMD) is an agency of the Ministry of Earth Sciences of the Government of India. It is the principal agency responsible for meteorological observations, weather forecasting and seismology. IMD is headquartered in Delhi and operates hundreds of observation stations across India and Antarctica.Regional offices are at Mumbai, Kolkata, Nagpur and Pune.
The storm further intensified into a severe cyclonic storm on November 11 and began to turn towards the northeast, as it approached the head of the bay. It developed a clear eye, and reached its peak intensity later that day, with 3-minute sustained winds of 185 km/h (115 mph), 1-minute sustained winds of 240 km/h (150 mph), and a central pressure of 960 hPa. The cyclone made landfall on the East Pakistan coastline during the evening of November 12, around the same time as the local high tide. Once over land, the system began to weaken; the storm degraded to a cyclonic storm on November 13, when it was about 100 km (62 mi) south-southeast of Agartala. The storm then rapidly weakened into a remnant low over southern Assam that evening.
The eye is a region of mostly calm weather at the center of strong tropical cyclones. The eye of a storm is a roughly circular area, typically 30–65 km (20–40 miles) in diameter. It is surrounded by the eyewall, a ring of towering thunderstorms where the most severe weather and highest winds occur. The cyclone's lowest barometric pressure occurs in the eye and can be as much as 15 percent lower than the pressure outside the storm.
Agartala is the capital of the Indian state of Tripura and is the second largest city and municipal body in northeastern India after Guwahati. The city is the seat of the Government of Tripura. Agartala is one of the fastest developing cities of India. There are 8 police stations and 9 legislative assembly constituencies covering various parts of the city.
Assam is a state in northeastern India, situated south of the eastern Himalayas along the Brahmaputra and Barak River valleys. Assam covers an area of 78,438 km2 (30,285 sq mi). The state is bordered by Bhutan and Arunachal Pradesh to the north; Nagaland and Manipur to the east; Meghalaya, Tripura, Mizoram and Bangladesh to the south; and West Bengal to the west via the Siliguri Corridor, a 22 kilometres (14 mi) strip of land that connects the state to the rest of India.
There is question as to how much of the information about the cyclone said to have been received by Indian weather authorities was transmitted to East Pakistan authorities. This is because the Indian and East Pakistani weather services may not have shared information given the Indo-Pakistani friction at the time.A large part of the population was reportedly taken by surprise by the storm. There were indications that the storm warning system that existed in East Pakistan was not used properly, which probably cost tens of thousands of lives. The Pakistan Meteorological Department issued a report calling for "danger preparedness" in the coastal regions in danger during the day on November 12. As the storm neared the coast, a "great danger signal" was broadcast on Pakistan Radio. Survivors later said that this meant little to them, but that they had recognised a No. 1 warning signal as representing the greatest possible threat.
The Pakistan Meteorological Department, is an autonomous and independent institution tasked with providing weather forecasts and public warnings concerning weather for protection, safety and general information. Apart from meteorology, it is also involved in monitoring as well as investigating weather phenomenons, astronomical events, hydrology and research in astrophysics, climate changes and studies on aeronautical engineering, renewable energy resources across various parts of the country. Headquartered in Islamabad, it has offices and research facilities in all provinces and territories of the country.
Following two previously destructive cyclones in October 1960 which killed at least 16,000 people in East Pakistan, the Pakistani government contacted the American government for assistance in developing a system to avert future disasters. Gordon Dunn, the director of the National Hurricane Center at the time, carried out a detailed study and submitted his report in 1961. However, the government did not carry out all of the recommendations Dunn had listed.
Although the North Indian Ocean is the least active of the tropical cyclone basins, the coast of the Bay of Bengal is particularly vulnerable to the effects of tropical cyclones. The exact death toll will never be known, but it is estimated to be 300,000 to 500,000 people in total. The Bhola cyclone was not the most powerful of these, however; the 1991 Bangladesh cyclone was significantly stronger when it made landfall in the same general area, as a Category 5-equivalent cyclone with 260 km/h (160 mph) winds.
The Bhola cyclone is the deadliest tropical cyclone on record and also one of the deadliest natural disasters in modern history. A comparable number of people died as a result of the 1976 Tangshan earthquake and the 2004 Indian Ocean earthquake, but because of uncertainty in the number of deaths in all three disasters, it may never be known which one was the deadliest.
|Sources: NOAA, MDR|
The meteorological station in Chittagong, 95 km (59 mi) to the east of where the storm made landfall, recorded winds of 144 km/h (89 mph) before its anemometer was blown off at about 2200 UTC on November 12. A ship anchored in the port in the same area recorded a peak gust of 222 km/h (138 mph) about 45 minutes later. As the storm made landfall, it caused a 10-metre (33 ft) high storm surge at the Ganges Delta. In the port at Chittagong, the storm tide peaked at about 4 m (13 ft) above the average sea level, 1.2 m (3.9 ft) of which was the storm surge.
Pakistani radio reported that there were no survivors on the 13 islands near Chittagong. A flight over the area showed the devastation was complete throughout the southern half of Bhola Island, and the rice crops of Bhola Island, Hatia Island and the nearby mainland coastline were destroyed. 1 m (3.3 ft) of water for several hours.Several seagoing vessels in the ports of Chittagong and Mongla were reported damaged, and the airports at Chittagong and Cox's Bazar were under
Over 3.6 million people were directly affected by the cyclone, and the total damage from the storm was estimated at $86.4 million (1970 USD, $450 Million 2006 USD). The survivors claimed that approximately 85% of homes in the area were destroyed or severely damaged, with the greatest destruction occurring along the coast. Ninety percent of marine fishermen in the region suffered heavy losses, including the destruction of 9,000 offshore fishing boats. Of the 77,000 onshore fishermen, 46,000 were killed by the cyclone, and 40% of the survivors were affected severely. In total, approximately 65% of the fishing capacity of the coastal region was destroyed by the storm, in a region where about 80% of the protein consumed comes from fish. Agricultural damage was similarly severe with the loss of $63 million worth of crops and 280,000 cattle. Three months after the storm, 75% of the population was receiving food from relief workers, and over 150,000 relied upon aid for half of their food.
The cyclone brought widespread rain to the Andaman and Nicobar Islands, with very heavy rain falling in places on November 8 and 9. Port Blair recorded 130 mm (5.1 in) of rain on November 8, and there were a number of floods on the islands. The MV Mahajagmitra, a 5,500-ton freighter en route from Calcutta to Kuwait, was sunk by the storm on November 12, with the loss of all 50 people on board. The ship sent out a distress signal and reported experiencing hurricane-force winds before it sank. There was also widespread rain in West Bengal and southern Assam. The rain caused damage to housing and crops in both Indian states, with the worst damage occurring in the southernmost districts.
Two medical relief surveys were carried out by the Pakistan-SEATO Cholera Research Laboratory: the first in November and the second in February and March. The purpose of the first survey was to establish the immediate medical needs in the affected regions, and the second, more detailed, survey was designed as the basis for long-term relief and recovery planning. In the second survey, approximately 1.4% of the area's population was studied.
The first survey concluded that the surface water in most of the affected regions had a comparable salt content to that drawn from wells, except in Sudharam, where the water was almost undrinkable with a salt content of up to 0.5%. The mortality was estimated at 14.2%—equivalent to a death toll of 240,000.Cyclone-related morbidity was generally restricted to minor injuries, but a phenomenon dubbed "cyclone syndrome" was observed. This consisted of severe abrasions on the limbs and chest caused by survivors clinging to trees to withstand the storm surge. Initially, there were fears of an outbreak of cholera and typhoid fever in the weeks following the storm, but the survey found no evidence of an epidemic of cholera, smallpox or any other disease in the region affected by the storm.
The totals from the second survey were likely a considerable underestimate as several groups were not included. The 100,000 migrant workers who were collecting the rice harvest, families who were completely wiped out by the storm and those who had migrated out of the region in the three months were not included, and by excluding these groups, the risk of hearsay and exaggeration was reduced. The survey concluded that the overall death toll was, at minimum, 224,000. The worst effects were felt in Tazumuddin, where the mortality was 46.3%, corresponding to approximately 77,000 deaths in Thana alone. The mean mortality throughout the affected region was 16.5%.
The results showed that the highest survival rate was for adult males aged 15–49, while more than half the deaths were children under ten, who only formed a third of the pre-cyclone population. This suggests that the young, old, and sick were at the highest risk of perishing in the cyclone and its storm surge. In the months after the storm, the mortality of the middle-aged was lower in the cyclone area than in the control region, near Dhaka. This reflected the storm's toll on the less healthy individuals.
The day after the storm struck the coast, three Pakistani gunboats and a hospital ship carrying medical personnel and supplies left Chittagong for the islands of Hatia, Sandwip and Kutubdia.Teams from the Pakistani army reached many of the stricken areas in the two days following the landfall of the cyclone. Pakistani President Yahya Khan returned from a state visit to China and overflew the disaster area on November 16. The president ordered "no effort to be spared" to relieve the victims. He also ordered that all flags should be flown at half-mast and announced a day of national mourning on November 21, a week after the cyclone struck land.
In the ten days following the cyclone, one military transport aircraft and three crop-dusting aircraft were assigned to relief work by the Pakistani government. million to finance relief operations in the disaster area. Yahya Khan arrived in Dhaka to take charge of the relief operations on November 24. The governor of East Pakistan, Vice Admiral S. M. Ahsan, denied charges that the armed forces had not acted quickly enough and said supplies were reaching all parts of the disaster area except for some small pockets.The Pakistani government said it was unable to transfer military helicopters from West Pakistan as the Indian government did not grant clearance to cross the intervening Indian territory, a charge the Indian government denied. By November 24, the Pakistani government had allocated a further $116
A week after the cyclone's landfall, President Khan conceded that his government had made "slips" and "mistakes" in its handling of the relief efforts. He said there was a lack of understanding of the magnitude of the disaster. He also said that the general election slated for December 7 would take place on time, although eight or nine of the worst affected districts might experience delays, denying rumours that the election would be postponed.
As the conflict between East and West Pakistan developed in March, the Dhaka offices of the two government organisations directly involved in relief efforts were closed for at least two weeks, first by a general strike and then by a ban on government work in East Pakistan by the Awami League. Relief work continued in the field, but the long-term planning was curtailed.
Political leaders in East Pakistan were deeply critical of the central government's initial response to the disaster. A statement released by eleven political leaders in East Pakistan ten days after the cyclone hit charged the government with 'gross neglect, callous indifference and utter indifference'. They also accused the president of playing down the news coverage. people on November 24, when he accused the president of inefficiency and demanded his resignation. The president's political opponents accused him of bungling the efforts and some demanded his resignation.On November 19, students held a march in Dhaka in protest of the speed of the government response, and Maulana Abdul Hamid Khan Bhashani addressed a rally of 50,000
The Pakistan Red Crescent began to operate independently of the government as the result of a dispute that arose after the Red Crescent took possession of 20 rafts donated by the British Red Cross.A pesticide company had to wait two days before it received permission for two of its crop dusters, which were already in the country, to carry out supply drops in the affected regions. The Pakistani government only deployed a single helicopter to relief operations, with Yahya Khan later stating that there was no point deploying any helicopters from West Pakistan as they were unable to carry supplies.
A reporter for the Pakistan Observer spent a week in the worst hit areas in early January and saw none of the tents supplied by relief agencies being used to house survivors and commented that the grants for building new houses were insufficient. The Pakistan Observer regularly carried front-page stories with headlines like "No Relief Coordination", while publishing government statements saying "Relief operations are going smoothly." In January, the coldest period of the year in East Pakistan, the National Relief and Rehabilitation Committee, headed by the editor of Ittefaq , said thousands of survivors from the storm were "passing their days under [the] open sky". A spokesman said families who were made homeless by the cyclone were receiving up to 250 rupees ( US$55 dollars in 1971; equivalent to $340in 2018) to rebuild, but that resources were scarce and he feared the survivors would "eat the cash".
The Awami League, headed by Sheikh Mujibur Rahman, swept to a landslide victory in the national elections in December 1970, in part because of dissatisfaction over failure of the relief efforts by the national government. The elections for nine national assembly and eighteen provincial assembly seats had to be postponed until January 18 as a result of the storm.
The government's handling of the relief efforts helped exacerbate the bitterness felt in East Pakistan, swelling the resistance movement there. Funds only slowly got through, and transport was slow in bringing supplies to the devastated regions. As tensions increased in March, foreign personnel evacuated because of fears of violence.The situation deteriorated further and developed into the Bangladesh Liberation War in March. This conflict widened into the Indo-Pakistani War of 1971 in December and concluded with the creation of Bangladesh. This was one of the first times that a natural event helped to trigger a civil war.
India became one of the first nations to offer aid to Pakistan, despite the generally poor relations between the two countries, and by the end of November had pledged $1.3 million (1970 USD, $6.9 million 2007 USD) of assistance for the relief efforts. The Pakistani government refused to allow the Indians to send supplies into East Pakistan by air, forcing them to be transported slowly by road instead. The Indian government also said that the Pakistanis refused an offer of military aircraft, helicopters and boats from West Bengal to assist in the relief operation.
US President Richard Nixon allocated a $10 million ($65 million in 2018) grant to provide food and other essential relief to the survivors of the storm, and the U.S. ambassador to Pakistan pledged that he would "assist the East Pakistan government in every way feasible." The American government also sent a number of blankets, tents and other supplies. Six helicopters, two helicopters at an aid mission in Nepal and four from the United States, were sent to East Pakistan. Some 200,000 tons of wheat were shipped from the United States to the stricken region. By the end of November, there were 38 helicopters operating in the disaster area, ten of which were British and ten American. The Americans had provided about 50 small boats and the British 70 for supply distribution.
CARE halted aid shipments to the country the week after the cyclone hit, because of unwillingness to let the Pakistani government handle distribution. million ($7 million in 2018). American concerns about delays by the Pakistani government in determining how the relief should be used meant that $7.5 million ($48 million in 2018) of relief granted by the US Congress had not been handed over in March. Much of the money was earmarked to be spent on constructing cyclone shelters and rebuilding housing. The American Peace Corps offered to send volunteers but were rebuffed by the Pakistani government.However, by January, they had reached an agreement to construct 24,000 cement brick houses at a cost of about $1.2
A Royal Navy task force, centred on HMS Intrepid and HMS Triumph , left Singapore for the Bay of Bengal to assist with the relief efforts. They carried eight helicopters and eight landing craft, as well as rescue teams and supplies. million (£23 million in 2018) for disaster relief in East Pakistan.Fifty soldiers and two helicopters were flown in ahead of the ships to survey the disaster area and bring relief work. The British task force arrived off the Pakistan coast on November 24, and the 650 troops aboard the ships immediately began using landing craft to deliver supplies to offshore islands. An appeal by the British Disasters Emergency Committee raised about £1.5
The Canadian government pledged $2 million of assistance. France and West Germany both sent helicopters and various supplies worth $1.3 million. Pope Paul VI announced that he would visit Dhaka during a visit to the Far East and urged people to pray for the victims of the disaster. The Vatican later contributed $100,000 to the relief efforts. By the start of 1971, four Soviet helicopters were still operating in the region transporting essential supplies to hard-hit areas. The Soviet aircraft, which had drawn criticism from Bengalis, replaced the British and American helicopters that had operated immediately after the cyclone.
The government of Singapore sent a military medical mission to East Pakistan which arrived at Chittagong on December 1, 1971. They were then deployed to Sandwip where they treated nearly 27,000 people and carried out a smallpox vaccination effort. The mission returned to Singapore on December 22, after bringing about $50,000 worth of medical supplies and 15 tons of food for the victims of the storm. The Japanese cabinet approved a total of $1.65 million of relief funds in December. The Japanese government had previously drawn criticism for only donating a small amount to relief work. The first shipment of Chinese supplies to East Pakistan was a planeload of 500,000 doses of cholera vaccine, which was not necessary as the country had adequate stocks. The Chinese government sent $1.2 million in cash to Pakistan. Mohammad Reza Pahlavi declared that the disaster was also an Iranian one and responded by sending two planeloads of supplies within a few days of the cyclone striking. Many smaller, poorer Asian nations sent nominal amounts of aid.
The United Nations donated $2.1 million in food and cash, while UNICEF began a drive to raise a further million. UNICEF helped to re-establish water supplies in the wake of the storm, repairing over 11,000 wells in the months following the storm. UN Secretary-General U Thant made appeals for aid for the victims of the cyclone and the civil war in August, in two separate relief programs. He said only about $4 million had been contributed towards immediate needs, well short of the target of $29.2 million. By the end of November, the League of Red Cross Societies had collected $3.5 million to supply aid to the victims of the disaster.
The World Bank estimated that it would cost $185 million to reconstruct the area devastated by the storm. The bank drew up a comprehensive recovery plan for the Pakistani government. The plan included restoring housing, water supplies and infrastructure to their pre-storm state. It was designed to combine with a much larger ongoing flood-control and development program. The Bank provided $25 million of credit to help rebuild the East Pakistan economy and to construct protective shelters in the region. This was the first time that the IDA had provided credit for reconstruction. By the start of December, nearly $40 million had been raised for the relief efforts by the governments of 41 countries, organisations and private groups.
In 1971, ex-Beatle George Harrison was inspired to organize The Concert for Bangladesh, in part from the 1970 Bhola Cyclone, and from the 1971 Bangladesh Genocide and Bangladesh Liberation War.Although it was the first benefit concert of its type, it was extremely successful in raising money, aid and awareness for the region's plight.
In December, the League of Red Cross Societies drafted a plan for immediate use should a comparable event to the cyclone hit other "disaster prone countries". A Red Cross official stated some of the relief workers sent to East Pakistan were poorly trained, and the organisation would compile a list of specialists. The UN General Assembly adopted a proposal to improve its ability to provide aid to disaster-stricken countries. In 1966, the Red Crescent had begun to support the development of a cyclone warning system, which developed into a Cyclone Preparedness Programme in 1972, today run by the Government of Bangladesh and the Bangladesh Red Crescent Society. The programme's objectives are to raise public awareness of the risks of cyclones and to provide training to emergency personnel in the coastal regions of Bangladesh.
In the 30 years after the 1970 cyclone, over 200 cyclone shelters were constructed in the coastal regions of Bangladesh. When the next destructive cyclone approached the country in 1991, volunteers from the Cyclone Preparedness Programme warned people of the cyclone two to three days before it struck land. Over 350,000 people fled their homes to shelters and other brick structures, while others sought high ground. While the 1991 cyclone killed over 138,000 people, this was significantly less than the 1970 storm, partly because of the warnings sent out by the Cyclone Preparedness Programme. However, the 1991 storm was significantly more destructive, causing 1.5 billion dollars in damage (2 billion inflation-adjusted) compared to the 1970 storm's 86.4 million dollars in damage.
The 1991 Bangladesh cyclone was among the deadliest tropical cyclones on record. On the night of April 29, 1991, it struck the Chittagong district of southeastern Bangladesh with winds of around 250 km/h (155 mph). The storm forced a 6-metre (20 ft) storm surge inland over a wide area, killing at least 138,866 people and leaving as many as 10 million homeless.
The 1999 Odisha cyclone was the strongest recorded tropical cyclone in the North Indian Ocean and among the most destructive in the region. The 1999 Odisha cyclone organized into a tropical depression in the Andaman Sea on 25 October, though its origins could be traced back to an area of convection in the Sulu Sea four days prior. The disturbance gradually strengthened as it took a west-northwesterly path, reaching cyclonic storm strength the next day. Aided by highly favorable conditions, the storm rapidly intensified, attaining super cyclonic storm intensity on 28 October, before peaking on the next day with winds of 260 km/h (160 mph) and a record-low pressure of 912 mbar. The storm maintained this intensity as it made landfall on Odisha on 29 October. The cyclone steadily weakened due to persistent land interaction and dry air, remaining quasi-stationary for two days before slowly drifting offshore as a much weaker system; the storm dissipated on 4 November over the Bay of Bengal.
The years before 1975 featured the pre-1975 North Indian Ocean cyclone seasons. Each season was an ongoing event in the annual cycle of tropical cyclone formation. The North Indian tropical cyclone season has no bounds, but they tend to form between April and December, peaks in May and November. These dates conventionally delimit the period of each year when most tropical cyclones form in the northern Indian Ocean. Below are the most significant cyclones in the time period. Because much of the North Indian coastline is near sea level and prone to flooding, these cyclones can easily kill many with storm surge and flooding. These cyclones are among the deadliest on earth in terms of numbers killed.
The 1970 North Indian Ocean cyclone season had no bounds, but tropical cyclones in the North Indian Ocean tend to form between April and December, with peaks in May and November. The 1970 season saw a total of seven cyclonic storms, of which three developed into severe cyclonic storms. The Bay of Bengal was more active than the Arabian Sea during 1970, with all of the three severe cyclonic storms in the season forming there. Unusually, none of the storms in the Arabian Sea made landfall this year. The most significant storm of the season was the Bhola cyclone, which formed in the Bay of Bengal and hit Bangladesh on November 12. The storm killed at least 500,000, making it the deadliest tropical cyclone in recorded history.
The 2008 North Indian cyclone season was one of the most disastrous seasons in modern history, with tropical cyclones leaving more than 140,000 people dead and causing nearly US$14 billion in damage. The season has no official bounds but cyclones tend to form between April and December. These dates conventionally delimit the period of each year when most tropical cyclones form in the northern Indian Ocean. There are two main seas in the North Indian Ocean—the Bay of Bengal to the east of the Indian subcontinent and the Arabian Sea to the west of India. The official Regional Specialized Meteorological Centre in this basin is the India Meteorological Department (IMD), while the Joint Typhoon Warning Center releases unofficial advisories. An average of four to six storms form in the North Indian Ocean every season with peaks in May and November. Cyclones occurring between the meridians 45°E and 100°E are included in the season by the IMD.
Cyclone Sidr was a tropical cyclone that resulted in one of the worst natural disasters in Bangladesh. The fourth named storm of the 2007 North Indian Ocean cyclone season, Sidr formed in the central Bay of Bengal, and quickly strengthened to reach peak 1-minute sustained winds of 260 km/h (160 mph), making it a Category-5 equivalent tropical cyclone on the Saffir-Simpson Scale. The storm eventually made landfall in Bangladesh on November 15, 2007, causing large-scale evacuations. At least 3,447 deaths have been blamed on the storm, with some estimates reaching 15,000.
The 2004 North Indian Ocean cyclone season was the first in which tropical cyclones were officially named in the basin. Cyclone Onil, which struck Pakistan, was named in late September. The final storm, Cyclone Agni, was also named, and crossed into the southern hemisphere shortly before dissipation. This storm became notable during its origins and became one of the storms closest to the equator. The season was fairly active, with ten depressions forming from May to November. The India Meteorological Department designated four of these as cyclonic storms, which have maximum sustained winds of at least 65 km/h (40 mph) averaged over three minutes. The Joint Typhoon Warning Center also issued warnings for five of the storms on an unofficial basis.
1991 (MCMXCI) was a common year starting on Tuesday of the Gregorian calendar, the 1991st year of the Common Era (CE) and Anno Domini (AD) designations, the 991st year of the 2nd millennium, the 91st year of the 20th century, and the 2nd year of the 1990s decade.
Extremely Severe Cyclonic Storm Nargis caused the worst natural disaster in the recorded history of Myanmar during early May 2008. The cyclone made landfall in Myanmar on Friday, 2 May 2008, sending a storm surge 40 kilometres up the densely populated Irrawaddy delta, causing catastrophic destruction and at least 138,373 fatalities. The Labutta Township alone was reported to have 80,000 dead, with about 10,000 more deaths in Bogale. There were around 55,000 people missing and many other deaths were found in other towns and areas, although the Myanmar government's official death toll may have been under-reported, and there have been allegations that government officials stopped updating the death toll after 138,000 to minimize political fallout. The feared 'second wave' of fatalities from disease and lack of relief efforts never materialized. Damage was estimated at over K62,988,000,000 (US$10 billion), which made it the most damaging cyclone ever recorded in this basin.
Cyclone Aila(JTWC designation:02B, also known as Severe Cyclonic Storm Aila) was the second named tropical cyclone of the 2009 North Indian Ocean cyclone season. Warned by both the Regional Specialized Meteorological Center (RMSC) and Joint Typhoon Warning Center (JTWC), Aila formed over a disturbance over the Bay of Bengal on 23 May, 2009 and started to intensify ando organize reaching 3-min sustained wind speeds of 110 kmh (70 mph). It was the worst natural disaster to affect Bangladesh since Cyclone Sidr in November 2007. A relatively strong tropical cyclone, it caused extensive damage in India and Bangladesh.
Very Severe Cyclonic Storm Giri was a powerful tropical cyclone which caused catastrophic damage in parts of Myanmar in late October 2010. Originating from an area of low pressure over the Bay of Bengal on October 19, the system began as a weak depression 250 km (155 mi) south of Myanmar. Over the following few days, the depression underwent explosive intensification, reaching its peak intensity with winds of 195 km/h on October 22. Cyclone Giri made landfall roughly 50 km (31 mi) northwest of Kyaukpyu, shortly after peaking. Within hours of moving onshore, the system had substantially weakened. By the following day, Giri had degenerated into a tropical depression and the final advisory was issued on the storm.
The 2002 West Bengal cyclone was a deadly tropical cyclone that affected India and Bangladesh in November 2002. The sixth tropical cyclone and fourth cyclonic storm of the 2002 North Indian Ocean cyclone season, it developed in the Bay of Bengal northeast of Sri Lanka on November 10, as a tropical depression. After tracking northeast, the system strengthened into a cyclonic storm on November 11, as maximum sustained winds exceeded 65 km/h (40 mph). On November 12, it further intensified into a severe cyclonic storm. Later that day, the storm made landfall on Sagar Island in West Bengal with winds of 100 km/h (65 mph). After moving inland, it rapidly weakened and dissipated over Bangladesh on November 12.
The 2004 Myanmar cyclone was considered the worst to strike the country since 1968. The second tropical cyclone of the 2004 North Indian Ocean cyclone season, it formed as a depression on May 16 in the central Bay of Bengal. With low wind shear and a surge in the monsoon trough, the storm intensified while meandering over open waters. The storm eventually began a steady northeastward motion due to a ridge to the north over India. While approaching land, an eye developed in the center of the storm, indicative of a strong cyclone. On May 19, the cyclone made landfall along northwestern Myanmar near Sittwe, with maximum sustained winds estimated at 165 km/h (105 mph) by the India Meteorological Department. The storm rapidly weakened over land, although its remnants spread rainfall into northern Thailand and Yunnan province in China.
The 1996 Andhra Pradesh cyclone was a small but powerful storm that left heavy damage in the Indian state of Andhra Pradesh. It formed on November 4 in the eastern Bay of Bengal. Moving westward, it quickly organized and developed a well-defined eye. On November 6, the cyclone struck about 50 km (30 mi) south of Kakinada, Andhra Pradesh at peak intensity. The India Meteorological Department estimated peak winds of 145 km/h (90 mph), while the American-based Joint Typhoon Warning Center (JTWC) assessed peak winds of 215 km/h (130 mph). Soon after landfall, the cyclone weakened and dissipated by November 7.
The 1988 Bangladesh cyclone was one of the worst tropical cyclones in Bangladeshi history. Striking in November 1988, the tropical system exacerbated the catastrophic damage from what was then considered the worst floods in Bangladesh's history. The tropical cyclone originated from a disturbance that developed within the Strait of Malacca on November 21. Tracking slowly westward, the initial tropical depression reached tropical storm status in the Andaman Sea. On November 26, the storm reached an intensity equivalent to that of a modern-day severe cyclonic storm and subsequently turned northward. Gradually intensifying as it had previously, the tropical cyclone reached peak intensity with winds of 125 mph (200 km/h) as it was making landfall near the Bangladesh-West Bengal border on November 29. Although the storm retained strong winds well inland, it was last monitored over central Bangladesh as a moderate cyclonic storm-equivalent on November 30.
Cyclonic Storm Komen was an unusual tropical cyclone that originated near the southern coast of Bangladesh and later struck the same country while drifting over the northern Bay of Bengal. The second named storm of the 2015 season, Komen brought several days of heavy rainfall to Myanmar, Bangladesh, and India. It formed as a depression on July 26 over the Ganges delta and moved in a circular motion around the northern Bay of Bengal. Komen intensified into a 75 km/h (45 mph) cyclonic storm and moved ashore southeastern Bangladesh on July 30. The system turned westward over land and was last noted over eastern India on August 2.
Severe Tropical Cyclone Winston was the most intense tropical cyclone in the Southern Hemisphere on record, as well as the strongest to make landfall in the Southern Hemisphere, with the possible exception of 1899's Cyclone Mahina in both regards. Winston is also the costliest tropical cyclone on record in the South Pacific basin. The system was first noted as a tropical disturbance on 7 February 2016, when it was located to the northwest of Port Vila, Vanuatu. Over the next few days, the system gradually developed as it moved southeast, acquiring gale-force winds by 11 February. The following day, it underwent rapid intensification and attained ten-minute maximum sustained winds of 175 km/h (110 mph). Less favourable environmental conditions prompted weakening thereafter. After turning northeast on 14 February, Winston stalled to the north of Tonga on 17 February. Due to a change in higher level steering, the storm drifted back to the west. In the process, Winston again rapidly intensified, reaching Category 5 intensity on both the Australian tropical cyclone scale and the Saffir–Simpson hurricane wind scale on 19 February. The storm passed directly over Vanua Balavu, where a national record wind gust of 306 km/h (190 mph) was observed.
The 2017 North Indian Ocean cyclone season was a below average season in the annual cycle of tropical cyclone formation. This season produced only three named storms, of which one only intensified into a very severe cyclonic storm. The North Indian Ocean cyclone season has no official bounds, but cyclones tend to form between April and December, with the two peaks in May and November. These dates conventionally delimit the period of each year when most tropical cyclones form in the northern Indian Ocean. The season began with the formation Cyclone Maarutha on April 15, and ended with the dissipation of a deep depression on December 9.
Intense Tropical Cyclone Idai was one of the worst tropical cyclones on record to affect Africa and the Southern Hemisphere. The long-lived storm caused catastrophic damage in Mozambique, Zimbabwe, and Malawi, leaving more than 1,000 people dead and thousands more missing. Idai is the second-deadliest tropical cyclone recorded in the South-West Indian Ocean basin, behind only the 1892 Mauritius cyclone. In the Southern Hemisphere, it currently ranks as the third-deadliest tropical cyclone on record, behind the aforementioned 1892 Mauritius cyclone and the 1973 Flores cyclone. The cyclone's exact death toll is expected to never be known.