Humans can neither change the sun's radiation nor the earth's orbit around the sun. But they can control the increase in the amount of greenhouse gases and its effect on the atmosphere. Only sphere the last hundred years the carbon dioxide concentration has been raised alarmingly in the atmosphere and we humans can be held responsible for this.

The main cause of the increase in carbon dioxide level in the atmosphere is the burning of fossil fuels Since the end of the 19th century, industrial activities increased rapidly giving rise to many factors. These factories required energy, which was produced through the combustion of coal. Besides coal, other sources of energy such as mineral oil and natural gas were also burned to heat our houses, run cars and airplanes or to produce electricity. Nowadays, about 85 million barrels of crude oil are burned daily. Every time a fossil raw material is burned, it releases carbon dioxide into the air.

Therefore, it is clear that more and more greenhouse gases like carbon dioxide are being generated worldwide by humans. Moreover, we are also strengthening the greenhouse effect by deforestation. which means cutting down trees. Every year enormous areas of forests are destroyed by people to obtain wood and to clear regions for mining and to create pasture. This loss of the forest causes dual problems. Trees that are burned up release large volumes of carbon dioxide gas into the air. On the other hand, as forests absorb a lot of carbon dioxide from the air and deliver oxygen instead, we also destroy an important storehouse of carbon dioxide when we clear forests.

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   26 March, our Independence Day, is the biggest state festival. The day is celebrated every year in the country with great enthusiasm and fervour. It is a national holiday. All offices, educational institutions. shops and factories remain closed on this day. The day begins with a 31 gun salute. Early in the morning the President and the Prime Minister on behalf of the nation place floral wreaths at the National Mausoleum at Savar. Then other leaders, political parties, diplomats, social and cultural organisations, educational institutions and freedom fighters pay homage to the martyrs. People from all walks of life also go there in rallies and processions. There are many cultural programmes throughout the day, highlighting the heroic struggle and sacrifice in 1971. The country also witnesses a spectacular parade of defence forces, border guards, police, ansars and the VDP (Village Defence Party) at the National Parade Ground near the National Parliament. In Bangabandhu National Stadium, school children, scouts and girl guides take part in various displays to entertain thousands of spectators. Educational institutions also organise their individual programmes. Sports meets and tournaments are also organised on the day, including the exciting boat race in the river Buriganga. In the evening, all major public buildings are illuminated with colourful lights. Bangla Academy, Bangladesh Shilpakala Academy and other socio-cultural organisations hold cultural functions. Similar functions are also arranged in other places in the country.

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   Meherjan lives in a slum on the Sirajganj Town Protection Embankment. Her polythene-roofed shelter looks like a cage. She is nearly 45 but looks more than her age. In front of her shelter, she is trying to make a fire to cook the day's only meal, Her weak hands tremble as she adds some fallen leaves and straw to the fire. The whispering wind from the river Jamuna makes the fire unsteady. The dancing of the flames reminds Meherjan of the turmoil in her life. Not long ago Meherjan had everything a family, cultivable land and cattle. The erosion of the Jamuna consumed all her landed property gradually. It finally claimed her only shelter during the last monsoon. It took the river only a day to demolish Meher's house, trees, vegetable garden and the bamboo bush. She had a happy family once Over the years, she lost her husband and her family to diseases that cruel hunger and poverty brought to the family. Now, she is the only one left to live on with the loss and the pain. The greedy Jamuna has shattered her dreams and happiness.

There are thousand others waiting to share the same fate like Meherjan. Bangladesh is a land of rivers that affect its people. Erosion is a harsh reality for the people living along the riverbanks. During each monsoon, many more villages are threatened by the roaring rivers like the Jamuna, the Padma and the Meghna. It is estimated that river erosion makes at least 1,00,000 people homeless every year in Bangladesh, In fact, river erosion is one of the main dangers caused by climate change. If we can't take prompt action to adapt to climate change, there will be thousands of more Meherjans in our towns and villages every year.

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  In the next class Ms Choudhury tells her students the story of Lipi. The year before last, Lipi, a 14-year old girl, was in class nine in a rural school in Rangpur. Lipi is the eldest of five children three daughters and two sons. Their father is a day labourer working on other people's land and mother is a homemaker and a part-time worker at other people's homes. The parents. particularly the mother, found it real difficult to raise five children on the small income the Father could earn. Perhaps that is why Lipi's father wanted to marry her off, But Lipi was not ready to accept what her parents wanted to impose on her. She wanted to pursue her education. Her mother stood by her, though secretly. When her father arranged her marriage with Tara Mia, the only son of a farmer in the same village, she became greatly upset. Tara Mia was a widower-illiterate, but well off. His father had a few acres of arable land and was influential in the village. The marriage seemed to be Inevitable.

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