Hoi An is often the highlight of someone’s visit to Vietnam. It is the only town to survive the ravages of 50 years of war unscathed and is famed for its historic buildings and charming riverside location. What is less well known however is just how at risk Hoi An is from climate change.
It’s location at the mouth of a river make it particularly vulnerable to flooding. During the rainy season which coincides with particularly high tides water levels can rise by more than 3m inundating large areas of the town. Even now there are usually 2 or 3 serious floods every year and numerous smaller ones. Climate change will only make this worse. Not only because of rising seas but also because extreme rainfall events and storms will become more common. A warmer atmosphere can hold more moisture, around 7% more with each 1C temperature rise. When this moist air reaches the land intense rainfall will result. Heavy rainfall events are projected to become more frequent in southern and central Vietnam. This is further compounded by deforestation in the mountains inland which causes the rain to run off far more quickly than previously. The city is rather limited as to the flood prevention measures it can take due to the towns listing as a UNESCO world heritage site. Yet unless urgent action is taken we risk losing this charming little town to the rising seas.
A similar fate is likely to befall the areas beaches too. I was shocked to see how much had eroded when I went to Cua Dai Beach. Last time I visited 2 years ago it was a beautiful expanse of sand. This time there was no beach left. Palm trees were falling into the sea and desperate attempts had been made to stop the rest of the sand disappearing. There was a line of huge sandbags to stop the sand shifting. Further down the beach the gardens of resorts were collapsing. Last autumn the sea moved 30m inland in a single month. Whilst the erosion is a natural phenomenon there is no doubt that it has been exacerbated by rising sea levels and removal of the forest which naturally bound the beach together in order to construct resorts.
The 30 km up the coast the city of Da Nang also faces an uncertain future due to climate change. The city has experienced somewhat of a boom over the past couple of decades. The population is growing 10 % annually and much of the new development has been concentrated along the coast or on other low lying areas alongside the river. With sea levels projected to rise by up to 3m over the course of the century the city will face some serious challenges. The city is aware of the dangers it faces and has set up a Climate Change Coordination Office to implement a plan for responding to climate change and sea level rise. However they can only adapt so much. Unless the world takes immediate steps to control global warming it is only a matter of time before Hoi An, Danang and thousands of other coastal towns and cities become unviable. Their future is literally in our hands.