The last decade has given an indication of what is in store for humanity when it comes to the weather. It has been the hottest in recorded history. Every continent has had its share of floods and fires, cyclones and hurricanes to the point where they've begun to be treated as the new normal. Bangladesh once had six seasons, now it barely has three, where summer is dominant.
One area that cannot be overlooked is construction. According to some international estimates, it is responsible for about 38 per cent of total global energy-related CO2 emissions. This has generated new interest in finding better ways to build accommodations that work with Nature as opposed to against it. Global warming, depending on which side one talks to, is a fact of life today. A change is always painful, and there is no size that fits all. Change however is evident in many countries where policymakers have taken cognizance of the fact that traditional building construction must be adapted to battle the elements in order to protect communities at the forefront of these climatic shocks.
Some estimates put the number of people at 1.6 billion, who will be living in as many as nearly a thousand cities by the year 2050 and will be exposed to very high temperatures. That figure, of course, is a projection but already urban dwellers are facing the music. Bangladeshis for instance have been battling sustained high temperatures for some time now, particularly in Dhaka city where greenery has reportedly dwindled to about 20 per cent and declining. It is necessary to rethink urban forestation and green spaces. Disastrous decisions by city authorities to cut down trees in some areas for the purposes of 'beautification' are only going to contribute to raising temperatures.
Natural shade provided by trees is a proven way of reducing heat in cities. The use of massive structures of concrete, stone, etc. on the other hand, captures solar heat which is a step in the wrong direction. Rather, one should think about what works. In Vietnam for instance, traditional housing designs "such as the optimum orientation of buildings, high-rise rooms, and large opening improve ventilation" have helped immensely. Again, the use of green roofs and reflective surfaces that deflect direct sunlight and help reduce temperatures in buildings. These are some of the ways urban planners in Bangladesh can make changes to reduce temperatures. Lower temperatures in buildings translate into lower energy bills for consumers and less headache for policymakers, who otherwise will constantly be at their wits' end to generate more and more power - an unsustainable situation.
Bangladesh is no stranger to natural disasters like droughts, flooding to name but a few. Access to clean drinking water is increasingly a problem and rainwater harvesting is a technology that is proven. It has proven to be invaluable at times of drought and floods - the collected water can be stored in tanks and used inside buildings and structures during period of drought. But is there any reflection of this in our policy design, either urban or rural? Policies need to be enacted, rules framed and monitoring done to make this possible. Rainwater is a gift from Nature and it is going to waste for a lack of vision on our part. These are just some of the ways countries are beginning to adopt into national policies to make life more liveable for their citizens. So, the authorities here can start to adopt proven designs and utilise them for the public sector which will act as technology demonstrators for private sector to follow.