What is climate change? What is it about and why should we be concerned? Let me try to explain a huge and complicated subject simply and briefly. Human activity is pumping more and more carbon dioxide (CO2) into the atmosphere. We produce CO2. When we drive a car or take a plane. Or run a manufacturing plant. Or use electrical appliances at home, because nearly all our electricity is generated from natural gas, which is a fossil fuel. The CO2 builds up in the atmosphere, traps heat from the sun, and causes the planet to warm up. Already, the Earth’s average temperature has gone up by 1 degree Celsius compared to pre-industrial times, over 100 years ago. One degree Celsius does not sound like much, but it is very significant. Furthermore, temperatures are continuing to rise, faster and faster. Ice sheets in Greenland and Antarctica are melting into the oceans, and this is raising sea levels around the world. The UN currently projects that sea levels will rise by up to one metre by the end of this century. One metre. About three feet, just 80 years from now. But the scientists’ estimates have been going up. So sea levels may quite possibly rise higher and faster than that. Global warming is also making the weather more extreme. Droughts are getting more severe and prolonged. Rainfall and storms are becoming more intense. Singapore is already feeling the impact. Our weather is palpably hotter. Rainstorms are heavier. And this will very likely worsen over the next few decades, within the lifetimes of many of us. A recent Swiss study found that by 2050, just 30 years from now, several cities in the world will experience unprecedented climate shifts. And it found that one of them will be Singapore. We must prepare for the impact of climate change on Singapore. There are many risks and consequences. New diseases, more frequent pandemics, food shortages, forced migration of displaced populations, and even wars. Because we are a low-lying island, Singapore is especially vulnerable to one grave threat, and that is rising sea levels. In the 1960s and 70s, floods were common in Singapore, especially during the rainy season. That is why Uncle Ng Ah Chye from Jalan Kayu, whom I told you about earlier, had to rescue so many stranded residents whenever it flooded. When we had high tides, monsoon drains in low-lying parts of Singapore would fill up almost to the brim, even if it was not raining. And if it did rain, it would flood. Gan Kim Yong told me when he was a child, his family lived in Hong Kong Street in Chinatown, where his father ran a shop. Hong Kong Street is next to this. This is Temple Street, but it looked like this also. When there was an exceptionally high tide, which happened a few times a year, the tide water would rise up from the drains onto the five-foot way in front of the shop even without rain. So his father had to build racks to stack up his goods, out of reach of the water. To Kim Yong, who was then a boy, this was great fun. I don’t think that is Gan Kim Yong. [ laughter ] But actually it was a serious matter. These old flooding problems are now largely resolved. We improved the drainage system. We required buildings to be built on higher platforms, at least three metres above the mean sea level. Three metres sounds a lot because most of us are less than two metres tall. But three meters is not actually that high, because at high tide, the water can go up as high as two metres above the mean sea level. That leaves just a one metre buffer to cope with other factors. For example, heavy rain. If it rains, it fills up a little bit, and you’re still ok, and the water has some where to go. Because of this one metre buffer, we have managed to deal with our flooding problems thus far. But, with global warming, if sea levels rise by one metre, our buffer is gone. Because when it is high tide, two metres above that, water is already reaching the five-foot way. We will have no more buffer. Because if heavy rain coincides with a high tide, the water will have nowhere to go. We will, literally, be in deep water! Like Bangladesh whenever they are hit by a cyclone. Or, to take an extreme example, like New Orleans, much of which is below sea level – here you can see how the city was completely flooded when Hurricane Katrina hit it in 2005. So what can we do? Three things: understand climate change, mitigate climate change, and adapt to climate change. Let me explain them one by one. First, we have to understand what climate change means specifically for Singapore. Is it hot weather, extreme weather, drought, intense rain, water levels, sea levels, and therefore what do we do. So we have set up a Centre for Climate Research Singapore, CCRS. I visited them earlier this year. They have a team of scientists and meteorologists, and supercomputers to model the weather and do research. They showed me the records they have, which go back more than a century. Including these old weather diaries – which I am looking at. They go back to the 1930s, which were meticulously kept at the weather station on Mount Faber. CCRS is cooperating with their counterparts in neighbouring countries to study in more detail how climate change is affecting Southeast Asia. They are finding that Singapore, being near the equator, is more vulnerable to climate change than the global model suggests. Second, we must mitigate climate change. What does mitigate mean? It means we must do our part to reduce CO2 emissions. Singapore has joined international efforts to reduce emissions. We are part of the Paris Climate Agreement, and we have committed to slow down and ultimately cap our CO2 emissions by around 2030. To help achieve this, last year we introduced a carbon tax. Each of us can do our bit to promote sustainability and mitigate climate change. Like remembering to switch off the lights, reducing waste, and reusing and recycling more. In Singapore, we generate a huge amount of waste – whether from excessive packaging, food waste, or electronic waste. These all have to be disposed of, and often incinerated, which then generates more CO2. Our landfill is at Pulau Semakau. But that will eventually fill up, and then we will need Bukit Semakau, and then Gunung Semakau! So we have to find a sustainable solution. This is where young Singaporeans have been doing their part. Like Farah Sanwari, who is passionate about sustainability. Farah co-founded Repair Kopitiam a few years ago, to teach others how to repair damaged electronic appliances, furniture, toys and clothing. So these items can gain a new lease of life and you can use them longer, instead of being thrown away prematurely. We need more young Singaporeans to be like Farah, to be problem-solvers, innovators, scientists, engineers, entrepreneurs. [ applause ] As the song suggests, be prepared to do our part. This is the Grand Challenge for their generation. Although Singapore may not be able to stop climate change by ourselves, we can contribute to solutions, and we must do our fair share. Then we can be credible asking others to reduce their emissions too, and work towards a global solution to climate change. Unfortunately, such a global solution is still very far off. So we must work for the best, but be prepared for the worst. Therefore, the third thing we must do, is to adapt to climate change, and especially rising sea levels. We will need local measures to protect individual buildings and developments – and we have been doing this. For example, we have built MRT stations with elevated entrances. When you enter an MRT station, you need to climb up a few steps before you go down the escalator. This is flood protection for our MRT system. If we need to raise our steps higher, we will do that one day. We also require new developments to be built on higher platforms, instead of building three metres above mean sea level like before, they must now be at least four metres above mean sea level. For critical infrastructure like Changi Airport Terminal 5 and Tuas Port, we are raising the platforms even higher, at least five metres above mean sea level. But local measures will not be enough. We have many older buildings. These cannot be lifted up, or transported to higher ground. In fact, large parts of Singapore are low-lying, and we need to protect these low-lying areas as a whole. Let me show you the topography of Singapore. This is a map of Singapore, showing the heights. The light green are the lowest areas. The dark green is a little bit higher. The beige are our hills, and the dark brown are our “mountains”! But there are not very many dark brown pieces, so I do not think we can all retreat to live on Bukit Timah! Now let me show you the lowest parts, which are up to four metres above mean sea level. That’s where all the blue stuff comes in. You see the island looks much smaller if those one day become at risk. When sea levels rise, all these parts will increasingly be at risk. Not underwater yet, but at risk like Chinatown used to be in the old days – high tide, rain, troubled. If you look carefully, there is a long stretch along the East Coast to the city. Zoom in a little bit, you might be able to see where your house is. Not only will property values be affected, but safety and liveability also. And it will not just be if your house is in the pink area you’re in trouble, but the whole city. Because roads and trains run through the low-lying areas; hospitals, schools, and workplaces are all there. We cannot lose a big chunk of our city and expect the rest of Singapore to carry on as usual. Therefore, beyond localised measures, we need to protect entire areas, and the way to do that is to build coastal defences. We have studied our whole coastline in detail, and we have divided it into different segments. Some are more vulnerable than others, and we need different strategies to protect each of them, and we will have to prioritise the work, starting with the more critical segments, and in particular, City-East Coast and also Jurong Island. I will talk about the City – East Coast, which is a long stretch comprising the city area, and then the eastern coastline. Let’s look at the city area first. We built the Marina Reservoir and Marina Barrage, to protect the city area from flooding. Many of us enjoy visiting the Marina Barrage, to picnic and fly kites on top of the Pump House, especially if we have little kids. But PUB did not build the Pump House for kite flying. Its real purpose is to house seven giant pumps. That is why it is so tall. When it rains heavily during high tide, these pumps pump water out of Marina Reservoir into the sea, so that rain falling in the city area can then drain into Marina Reservoir. When sea levels rise, one Pump House will not be enough. We will need to build a second pump house on the opposite end of the Barrage. PUB has planned for this. So that’s for the city. For the eastern coastline, we will need possibly other solutions. We have looked at other countries for inspiration. In particular, we studied the Netherlands. The word “Netherlands” itself means “low-lying lands”. “Nether” – “low-lying”, lands. Half of the country is at most 1 metre above sea level. In fact, one quarter (27%) of their land is actually below sea level, what the Dutch call “polders”. Polders is land – this is one of them – that the Dutch have reclaimed from the sea. They first build a seawall in the water, enclose an area. Then they pump out the water behind the seawall to create dry land, and that dry land can be lower than sea level – and they have to keep pumping water out. The Dutch are famous for their windmills. But do you know why the Dutch originally built windmills? It was not to take tourist pictures. It was to pump water out from polders and keep the land dry. I do not think windmills will do very well in Singapore. The only windmill we had in Singapore was at Holland Village, and even that is gone now. But, polders are a serious option for us. We are building a small polder at Pulau Tekong, to gain some experience operating one. This is in the north-west part of Pulau Tekong, if you come in from the north to land at Changi you can see we are building the sea wall here. We will enclose the sea, and level off the land behind that, and pump out the water, and this will be a polder. We will use the new land for SAF training. Polders are one option to protect our eastern coastline. Instead of just building a seawall along the coastline, you extend out with a polder, build a seawall further out, you not only protect existing low-lying areas. But you extend out and create more land reclaimed from the sea which we can use for housing and other valuable purposes. That is one possible solution for the East Coast, to build polders along the coastline. But there are other alternatives. For example, we could reclaim a series of islands offshore, from Marina East all the way to Changi. We join up the islands, connect them up with barrages, and create a freshwater reservoir behind them, which will be similar to Marina Reservoir. This solution will make PUB very happy because we will have another big reservoir and it will enhance our water resilience. Our four taps will become more reliable. What I showed you are just artists’ impressions, I prepared them for this speech to give you a sense of the possibilities. We have not done engineering drawings yet. We will examine all the options carefully, and when the time comes, we will decide what is the best way to do it. This problem has good engineering solutions, although they will all cost money. How much will it cost, to protect ourselves against rising sea levels? My guess is probably $100 billion over 100 years, quite possibly more. If we only have 10 years to solve the problem, we will not have enough time or resources to do it. But because this is a 50 to 100-year problem, we can implement a 50 to 100-year solution to this problem. In Singapore, for long-term problems, we can make long-term solutions. Not everywhere, but in Singapore, yes, we can. [ applause ] We should treat climate change defences like we treat the SAF – with utmost seriousness. Work steadily at it, maintain a stable budget year after year, keep your eye on the target and do it over many years and several generations. That way we can afford it, and when we need it, we will have it ready. Both the SAF and climate change defences are existential for Singapore. These are life and death matters. Everything else must bend at the knee to safeguard the existence of our island nation. There is one difference between the two. With the SAF, we hope never to go to war. If you have a strong SAF, you may deter threats and avoid having to go to war. But with climate change, we know for sure sea levels will rise. The only uncertainty is whether they rise a few decades earlier, or a few decades later. Therefore, we will implement our climate change plans progressively, and keep them flexible. But we must start now and sustain the effort, as the Dutch have done over the centuries, and as we have done with the SAF. We must make this effort. Otherwise one day, our children and grandchildren will be ashamed of what our generation did not do.