2011 Thailand Floods

My climate region is Thailand, which has a tropical environment due to its proximity to the equator. With that being said, you can expect to experience warm temperatures year-round here. Another big factor that controls the climate here is the monsoons, which have distinct dry and wet seasons because of the Asian monsoon system. Three distinct seasons appear in Thailand: the hot season, the cool season, and the rainy season. The rainy season in Thailand is heavily impacted by the Southwest monsoon, which brings moist air from the Indian Ocean over the country of Thailand. The heaviest rainfall occurs in August and September, with the northern and western regions receiving more rainfall than the Southern and Eastern parts of Thailand. Temperatures are cooler during this time of year with temperatures ranging from 25° C to 30° C. During the cool season, temperatures are more manageable, with values from 20° C to 30° C. The cool season is known to be most popular for tourists, and it lasts from November through February. In addition, this season has the most rainfall of all of the other seasons, which makes it the best time of year for sightseeing and recreational activities. Beginning in March and ending in May is when the hot season typically ranges, with temperatures well above 30 degrees Celsius, and even reaching temperatures of up to 40 degrees Celsius at times, and in certain areas. Thailand is located in Southeast Asia and borders the countries of Myanmar, Vietnam, and Cambodia. It looks like a lush green tropical rainforest with many rivers, streams, and waterways. The country has both dense human and plant and animal populations. The climate is known to be very hot, humid, and sticky, with long average day lengths and lots of sunlight. Thailand is a place that needs to be explored, researched, and protected as it offers wonders of the world that are found nowhere else. Ultimately the cyclones determine the seasons and control the temperature values in Thailand and the surrounding region. Thailand is known to have a very tropical climate, with great temperature variations in the center of the country as well as the northern regions. These parts of the country also experience monsoons which are typical for this region of Southeast Asia. The country is known to have three distinct seasons, the wet season, the cool season, and the hot season(Climate). The wet season starts in May and ends in October, while the hot season starts in March and ends in May. Finally, the cool season starts in November and ends in February. Winter is characterized as an arid and cool season, during this time of the year the northeast monsoon prevails. The hot season is characterized as warm and sticky, and the rainy season is determined by the southwest monsoon, which generally starts in the middle of May and ends in October. In the South, there is a particularly different rainy season as there is a different weather pattern in this continent(Climate). Thailand’s weather is controlled by the cyclone season, with typhoons from June through December. Cyclones are the most common from September to November when the oceans are warmer(Nam 2020).

Since Thailand is located in a tropical area it's influenced by seasonal monsoons. 2011 was a year of heavy monsoon rains that started as early as July of that year. In addition, the region experienced record precipitation in March and April beforehand. With almost 6 months of above-average rainfall during the monsoon season and four tropical storms that were crossing the northern portion of the country at the time. This unexpected heavy precipitation led to mudslides and flooding which engulfed temples, villages, farms, and factories. The amount of rainfall that occurred in 2011 in Thailand was the highest in the country's 61-year precipitation record. The 2011 Thailand floods were the worst in modern Thai history, as approximately 9.1% of the total land area of the country was affected, along with over 13 million people. This natural disaster caused the deaths of 680 Thai people and had a paralyzing effect on the country's economy afterward. This disaster ranks fourth among the world’s costliest disasters as it was estimated that there were $46.5 billion in economic losses and damages. The flooding started because of the landfall from a previous Tropical Storm Nock-ten.  

With noticeably large amounts of precipitation during March and April, a rainy 6-month monsoon season, as well as Tropical Storm Nock-ten which hit Northern Thailand. Nock ten brought extreme precipitation and flash floods to northern and northeastern Thailand on July 31st. Within one week, 16 provinces were experiencing ongoing flooding, with 13 deaths already being reported as well. W

The flooding was still going on at the end of August due to a longer-than-expected multi-year La Nina event. In Downtown Nan, flood waters reached a depth of 20 inches, while other downtown provinces saw the death toll rise to 37 by August 22nd. The Sirikit and Bhumibol dams increased their discharge rates to help aid the increased water flow due to the floods.

By September, most of the country had been affected by the flood in one way or another. The floods caused broken floodgates which led to water from the Chao Phraya ending up in the paddy fields of Ayutthaya, Ang Thong, and Singburi. As an attempt to increase the river's discharge rate, power boats were used to push water against the river's normal flow.

By the beginning of October, the majority of the dams were forced to increase their rate of discharge due to already near or over capacity. This actually seemed to cause worse downstream flooding surprisingly, while flooding worsened in and around Ayutthaya, forcing evacuations. Lots of the barriers protecting the city were crushed by the flood water, which resulted in the flooding of dozens of factories and caused a disruption of the supply chain system in Thailand. However, the sandbag barrier protecting the city of Nakhon Sawan was destroyed resulting in the rapid flooding of the city, and the surrounding area.

The city of Bangkok became seriously threatened by the floods in mid-october, and by October 20th the floodwaters had rushed through the city. The entire campus of Thammasat University was flooded with 2 m of water, and was previously identified as an evacuation center. As the situation worsened several other flood gates had failed releasing even more water into residential areas. 

November saw lots of significant flooding in Thailand Southern provinces, where certain districts were even listed as disaster zones with flood waters reaching as high as 15 m in all areas. More than 159 roads were declared impossible, forcing many citizens to only escape by boat.

The precipitation that occurred in 2011 was the highest ever recorded for the country of Thailand, with approximately 23% above the normal precipitation levels. This precipitation was only fuel for the 2011 floods which destroyed the country of Thailand and its economy.

March and April of 2011 saw record levels of precipitation in Thailand, with an above-normal amount of rainfall during the monsoon season, which began in July of that year. With four tropical storms that were at the time sweeping the northern part of the nation, and nearly six months of monsoon season rainfall that was above average. This sudden, intense rain caused mudslides and flooding that destroyed factories, farms, communities, and temples. In Thailand's 61-year precipitation record, 2011 saw the most rainfall ever recorded in the country.

In 2011, Thailand experienced the remnants of four different tropical storms. These storms brought torrential rainfall, and caused extreme flooding in northern and Northeast Thailand, which later spread throughout the rest of the country These storms along with the monsoons, and the increased precipitation was the perfect combination for an profound flood of this caliber. 

The 2011 Thailand floods were caused by a combination of variables including the remnants of four tropical storms, an increased amount of precipitation, and because of the powerful southeast Asian monsoon. The floods will rank as the country's most expensive and destructive flood since it has been recorded. The unusually high precipitation resulting from the monsoon season combined with the highest annual rainfall in 61 years, led to the deaths of hundreds of Thai people. It is estimated that a return period for a flood of that caliber will be between 10 and 20 years. If flood defense, flood management, and flood prevention improved, then floods like this could be prevented in the first place. The 2011 floods in Thailand were the worst in the country's modern history, affecting nearly 13 million people and roughly 9.1% of the country's total geographical area. 680 Thais lost their lives in this natural tragedy, which also crippled the nation's economy in the aftermath. With an estimated $46.5 billion in economic losses and damages, this disaster is ranked fourth among the most costly in history. The landfall of a prior Tropical Storm Nock-ten caused the flooding to begin.