Environmental Impacts
Climate-wise in Bangladesh, three distinct seasons can be observed. A cool and dry season from November-February, a pre-monsoon hot season from March-May, and a rainy monsoon season from June-October [6].
Some information about each [8]:
Cool and dry season: As it suggests, Bangladesh is cool and dry during this season due to a high pressure area that moves in from India. It is during this season that droughts most often occur.
Pre-monsoon hot season: This season has high temperatures and frequent thunderstorms, and wind speed gradually increases as the season goes on. The frequent thunderstorms occur due to a low pressure area brought on by the high amount of direct sunlight warming up the area.
Rainy monsoon season: This season experiences winds coming from the south, high humidity, and many consecutive rainy days known as a monsoon. Similar to the pre-monsoon season, this occurs due to a low pressure area.
Some information about each [8]:
Cool and dry season: As it suggests, Bangladesh is cool and dry during this season due to a high pressure area that moves in from India. It is during this season that droughts most often occur.
Pre-monsoon hot season: This season has high temperatures and frequent thunderstorms, and wind speed gradually increases as the season goes on. The frequent thunderstorms occur due to a low pressure area brought on by the high amount of direct sunlight warming up the area.
Rainy monsoon season: This season experiences winds coming from the south, high humidity, and many consecutive rainy days known as a monsoon. Similar to the pre-monsoon season, this occurs due to a low pressure area.
The most critical factor resulting from climate change and impacting Bangladesh is rising sea levels. It is responsible for many of the social, economic, and political impacts that are discussed on following pages.
But firstly, how do we know that sea levels are even rising? Slide 1 on the slideshow below shows a graph depicting how sea levels have been rising steadily over time, and how the trend is expected to continue into the future [9].
Slide 2 then displays an info-graphic showcasing the causes of rising sea levels [10], while slide 3 explains how the cycle of melting glaciers (and therefore rising sea levels) will only increase at a faster rate over time [11].
Finally, slides 4 & 5 show the potential impact of rising sea levels in Bangladesh [12,13]. As Bangladesh really is such a low-lying country (slide 5), it is very easy for it to be affected by rising water levels.
But firstly, how do we know that sea levels are even rising? Slide 1 on the slideshow below shows a graph depicting how sea levels have been rising steadily over time, and how the trend is expected to continue into the future [9].
Slide 2 then displays an info-graphic showcasing the causes of rising sea levels [10], while slide 3 explains how the cycle of melting glaciers (and therefore rising sea levels) will only increase at a faster rate over time [11].
Finally, slides 4 & 5 show the potential impact of rising sea levels in Bangladesh [12,13]. As Bangladesh really is such a low-lying country (slide 5), it is very easy for it to be affected by rising water levels.
In the past, many of these factors, actions, and impacts to the environment were occurring due to climate change:
- many rivers run throughout the country and are prone to flooding in the rainy season [14]
- it is overall a very low-lying country, meaning the widespread flooding is both possible and expected (during the rainy season, 65% of the country becomes flooded) [15]
- cyclones, storm surges, droughts, and floods are periodic but expected [16]
- deforestation occurs to make room for urbanization
- industries were unchecked for pollutants and thus contributed many greenhouse gases to the atmosphere, increasing global warming
In the present, the effects are becoming more evident:
- saltwater intrusion is poisoning groundwater [17]
- dam construction and melting snow and ice from the Himalayas leads to river erosion and shifts in river flow [18]
- sea levels are rising due to the melting of the ice caps
- melting ice caps are a vicious cycle that will only get worse: when the ice caps melt, the albedo of the area is lowered and less energy is reflected, in fact it is absorbed. This warms the area, melting even more of the ice caps, and the vicious cycle continues
- regular flooding now leaves behind salt deposits that poison the land and make it unfit for farming [19]
- deforestation continues to occur as people are increasingly displaced by flood waters and rising sea levels, and are forced to move to other areas
- the emission of greenhouse gases are more closely monitored currently, however they are still being emitted [20]
In the future, the effects are expected to continue and resemble things such as:
- weather is expected to worsen as climate change causes stronger storms and more extreme weather: this is because warmer weather is caused by greenhouse gases absorbing energy. These greenhouse gases can transfer large amounts of energy quickly, and they cause the air to become warmer, which allows it to absorb more moisture. More moisture in the air means more potent and extreme weather.
- water levels are expected to rise around 2.9 meters by 2100 - this is disastrous as much of Bangladesh is low-lying and the entire country is about 10 meters at the most above sea level [21]
- flooding and increased deforestation (due to people being displaced by the rising water and needing somewhere to live) will mean that forest-dwelling species in Bangladesh will also be displaced or become locally endangered species [22]
1 "World Biomes." Web. 1 Nov. 2014.
2 Greenfield Geography. Web. 2 Nov. 2014.
3 "Banglapedia." Banglapedia. Web. 3 Nov. 2014.
4 Husain, Syed. "Plant and Animal Life."Encyclopedia Britannica Online. Encyclopedia Britannica. Web. 3 Nov. 2014.
5 Ibid.
6 "Banglapedia." Banglapedia. Web. 3 Nov. 2014.
7 Im-not-a-blogger. Web. 4 Nov. 2014.
8 "Banglapedia." Banglapedia. Web. 3 Nov. 2014.
9 "Rising Sea Levels." American Education. Web. 4 Nov. 2014.
10 "Why Sea Levels Rise." Enviro. Web. 2 Nov. 2014.
11 "Positive Feedback Loop." Geography Explained. Web. 2 Nov. 2014.
12 "Impact of Rising Sea Levels." Grida. Web. 2 Nov. 2014.
13 "Bangladesh at Risk." Web. 2 Nov. 2014.
14 "Bangladesh Is Drowning Because of Climate Change." The Huffington Post. N.p., n.d. Web. 28 Oct. 2014. <http://www.huffingtonpost.ca/alex-mifflin/bangladesh-climate-change_b_4150220.html
15 "Global Development of Climate Change."The Guardian. N.p., n.d. Web. 27 Oct. 2014. <http://www.theguardian.com/global-development/2014/mar/10/climate-change-talks-bangladesh-donors>.
16 Ibid.
17 "Global Development Climate Change." The Guardian. Web. 27 Oct. 2014.
18 Harris, Gardiner. "Borrowed Time on Disappearing Land." The New York Times. The New York Times, 28 Mar. 2014. Web. 28 Oct. 2014.
19 Ibid.
20 "Geography." Infoplease. Infoplease. Web. 4 Nov. 2014.
21 "Welcome to Bangladesh." Virtual Bangladesh. Web. 4 Nov. 2014.
22 "Bangladesh Facts, Bangladesh Flag -- National Geographic." National Geographic. Web. 1 Nov. 2014.
2 Greenfield Geography. Web. 2 Nov. 2014.
3 "Banglapedia." Banglapedia. Web. 3 Nov. 2014.
4 Husain, Syed. "Plant and Animal Life."Encyclopedia Britannica Online. Encyclopedia Britannica. Web. 3 Nov. 2014.
5 Ibid.
6 "Banglapedia." Banglapedia. Web. 3 Nov. 2014.
7 Im-not-a-blogger. Web. 4 Nov. 2014.
8 "Banglapedia." Banglapedia. Web. 3 Nov. 2014.
9 "Rising Sea Levels." American Education. Web. 4 Nov. 2014.
10 "Why Sea Levels Rise." Enviro. Web. 2 Nov. 2014.
11 "Positive Feedback Loop." Geography Explained. Web. 2 Nov. 2014.
12 "Impact of Rising Sea Levels." Grida. Web. 2 Nov. 2014.
13 "Bangladesh at Risk." Web. 2 Nov. 2014.
14 "Bangladesh Is Drowning Because of Climate Change." The Huffington Post. N.p., n.d. Web. 28 Oct. 2014. <http://www.huffingtonpost.ca/alex-mifflin/bangladesh-climate-change_b_4150220.html
15 "Global Development of Climate Change."The Guardian. N.p., n.d. Web. 27 Oct. 2014. <http://www.theguardian.com/global-development/2014/mar/10/climate-change-talks-bangladesh-donors>.
16 Ibid.
17 "Global Development Climate Change." The Guardian. Web. 27 Oct. 2014.
18 Harris, Gardiner. "Borrowed Time on Disappearing Land." The New York Times. The New York Times, 28 Mar. 2014. Web. 28 Oct. 2014.
19 Ibid.
20 "Geography." Infoplease. Infoplease. Web. 4 Nov. 2014.
21 "Welcome to Bangladesh." Virtual Bangladesh. Web. 4 Nov. 2014.
22 "Bangladesh Facts, Bangladesh Flag -- National Geographic." National Geographic. Web. 1 Nov. 2014.