Rising sea levels: A tale of two cities     * Introduction     * Maputo <http://news.bbc.co.uk/1/hi/world/africa/8363045.stm     * Rotterdam <http://news.bbc.co.uk/1/hi/sci/tech/8362147.stm     * Adaptation <http://news.bbc.co.uk/1/hi/world/africa/8366538.stm By Michael Hirst in Rotterdam and Kate McGeown in Maputo Composite image of Maestland storm barrier in the Netherlands and Mozambique coastline *When people talk about the impact of rising sea levels, they often think of small island states that risk being submerged if global warming continues unchecked.* But it's not only those on low-lying islands who are in danger. Millions of people live by the sea - and are dependent on it for their livelihoods - and many of the world's largest cities are on the coast. By 2050 the number of people living in delta cities is set to increase by as much as 70%, experts suggest, vastly increasing the number of those at risk. To shed light the impact of rising sea levels, we are taking a close look at two very different cities, Rotterdam <http://news.bbc.co.uk/2/hi/science/nature/8362147.stm and Maputo <http://news.bbc.co.uk/2/hi/africa/8363045.stm , and their varying responses to the problem. Infographic about sea level rises *Glaciers:* If the world's mountain glaciers and icecaps melt, sea levels will rise by an estimated 0.5m *Thermal expansion:* The expansion of warming oceans was the main factor contributing to sea level rise, in the 20th Century, and currently accounts for more than half of the observed rise in sea levels *Ice sheets:* These vast reserves contain billions of tonnes of frozen water - if the largest of them (the East Antarctic Ice Sheet) melts, the global sea level will rise by an estimated 64m Much of Rotterdam - Europe's busiest port city - lies several metres below sea level, and this vulnerable position has led it to develop some of the best flood protection in the world. As the capital of Mozambique - one of the world's poorest countries, and one that is already feeling the effects of climate change - Maputo is struggling to provide cost-effective measures to mitigate the effects of the rising waters. Authorities in both cities know urgent action is needed to protect their populations, and both are trying to rise to the challenge. *Weaker Gulf Stream* graph A rise in temperatures around the world due to carbon emissions since the industrial revolution means many icecaps and glaciers are steadily melting. Rising temperatures have also caused ocean waters to expand - the main cause of sea level rise in the 20th Century. The 2007 Intergovernmental Panel on Climate Change (IPCC) <http://www.ipcc.ch/ projected a likely sea level rise of 28-43cm this century, but it acknowledged that this was probably an underestimate, as not enough was known about how ice behaves. The fact that sea levels are rising is a major reason for concern and it's a combination of the global average rise together with the natural variability leading to larger regional rises, said Dr John Church, from Australia's government-funded science and research body, the CSIRO. The weakening of the Gulf Stream coupled with the gravitational effects of being closer to the North Pole mean waters in the northern hemisphere are experiencing the biggest rise. Green roof in Rotterdam, pic courtesy of Rotterdam Climate Initiative Rotterdam is promoting the use of green roofs to collect rain water Off the Netherlands, for example, sea levels rose by some 20cm in the last 100 years. But the country's national Delta Commission predicts they will increase by up to 1.3m by 2100 and by as much as 4m by 2200. There is a problem and we have to find an answer, said Rotterdam's Vice-Mayor Lucas Bolsius. We need to invest. If we don't put money into this issue we'll have a problem surviving. *Cyclones* The Dutch drew this conclusion from a massive storm surge in 1953, which caused widespread flooding and killed nearly 2,000 people. They set about defending populated areas with a massive network of dykes and dams, and experts now estimate the country is protected from all but a one-in-10,000-year event. The story is very different in Mozambique. Already buffeted by regular floods and cyclones, the problem of rising sea levels is one the authorities in Maputo could do without. But Mozambique has been identified as one of the countries likely to be affected most by climate change, and the issue will not go away. Mozambique coastline Much of what Mozambique would like to do is deemed too expensive While scientists cannot give an exact figure of how much the sea has already risen in Mozambique, the effects are already obvious. I went to the beach a lot as a child, and I've noticed things are changing, said 34-year-old Jose, who lives in Maputo. The water is eating the land - little by little it's eating the land. Mozambique has compiled an action plan, and has been offered help from the World Bank, UN agencies and a plethora of other aid agencies. But so far little has been done, and much of what the country would like to do is beyond its budget. I think people are still at the stage of 'Oh my God - what are we going to do?' as environmentalist Antonia Reina puts it. Mozambique will be going to the Copenhagen summit as part of a united African delegation, to ask for help from richer countries - like the Netherlands. Africa argues that climate change - including rising sea levels - is a global problem, and demands a global response. While most would agree with that sentiment, the reality is that every country has its own battles to face - and in this series of articles we examine how our two cities are coping, both at an individual and a municipal level, as the waters rise.     * Maputo     * Rotterdam <http://news.bbc.co.uk/1/hi/sci/tech/8362147.stm     * Adaptation <http://news.bbc.co.uk/1/hi/world/africa/8366538.stm By Kate McGeown BBC News, Maputo, Mozambique Ana Tembe and children *When Ana Tembe looks out to sea from her tiny straw shack, she knows she is living on borrowed time.* She is almost surrounded by water, and at least once a year it seeps through the cracks into her home. Year by year the problem is getting worse, and Ana is worried. I want my children to be safe, she said. We really need to relocate somewhere else, but we've got no money and no choice. Mozambique's government is trying to help people like Ana Tembe, who are not only in abject poverty, but are also at risk from floods, rising sea levels and coastal cyclones - all of which are caused or exacerbated by climate change. Numerous studies have been commissioned, carefully detailing the problems the country faces, and suggesting ways to combat these problems or adapt to the new reality. Erosion on the coast In pictures: Changes in Maputo <http://news.bbc.co.uk/2/hi/africa/8366064.stm Mozambique is widely cited as one of the countries most affected by climate change - and one of the key concerns is rising sea levels. The country has one of the longest coastlines in Africa, stretching 2,700 km (1,650 miles). About 13 million people live in coastal areas, and even more live in river deltas. Mozambican people are already suffering, said Environment Minister Alcinda Abreu. Climate change will affect their living conditions and also their dignity , she added. *Making a start* Compared with other poor countries, Mozambique is often lauded as a nation that has engaged with the issue of climate change and is trying to do something about it. But while a lot of work has been done on paper, far less has been done on the ground. Of the few projects already under way, one of the most obvious is a large embankment just north of the capital, Maputo, which the government has constructed in order to protect a main road. Environment Minister Alcinda Abreu *Developed countries have responsibilities, and we expect these countries to assume such responsibilities in Copenhagen* Environment Minister Alcinda Abreu Further down the coast, the oldest and most established slum area, Mafalala, has been equipped with a large drainage channel, preventing annual flooding and the knock-on effects of disease and destitution. We know how serious climate change is, and we're trying to do our best to find solutions, said Councillor Mario Macaringue, one of the main instigators of these projects. But he admits these interventions are just scratching the surface of the problem. We're trying lots of different things because we weren't prepared for so many changes in such a short space of time, he said. *Realistic possibilities* Some of these solutions have proved far too expensive to sustain. As I walked up the coastal road, for example, I found that the new embankment quickly petered out. It's made of concrete, and we were paying about $1,000 per metre, Mr Macaringue said. We need to find a cheaper alternative. If keeping people's homes safe from the rising waters is not an option, another possibility is to move them to higher ground. The government has already started relocating people - mainly as a result of the exceptionally large floods in 2000. But to move a family like Ana Tembe's, the government needs to provide more than just a house, the people need a livelihood as well. Given that most people fish or farm for a living - and the best place to do that is by a river or the sea - it is hard to find a suitable area which is any less vulnerable as the area they have just left. Embankment near Maputo Concrete embankments are too expensive to use in most areas If people cannot make a living, they become dependent on aid or move back again, leaving their new homes empty - as has already happened in some areas of Mozambique. Relocating people is difficult, and generally very expensive, said Matthias Spaviolo from UN Habitat, the United Nations agency for human settlements. *Impossible task?* All this is a big challenge for a country still recovering from a civil war, the devastating floods of 2000, as well as a series of cyclones and droughts. Professor Antonio Queface, one of the authors of a national report on the impact of climate change, says there are some things Mozambique can do alone. One of the key things we can do is monitor land use. We can avoid building more dwellings in areas at risk, he said. The other thing is education, so people know what risks they run. New drainage channel in Mafalala slum area Maputo councillors have installed a new drainage channel in Mafalala slum But he added that other solutions would simply not work without substantial investment in infrastructure - something the West would need to help with. Ms Abreu agrees. What we need is more resources - in terms of financial resources, the transference of technologies and building a national capacity to deal with the issues provoked by climate change, she said. Mozambique is going to the Copenhagen climate summit next month to lobby for these things - as part of a united African delegation determined to win compensation for the damage caused by global warming. Developed countries have responsibilities, said Ms Abreu, and we expect these countries to assume such responsibilities in Copenhagen. Her opinion is echoed on the streets of Maputo. The world is like a family, said Atanasio Muchanga, who lives near the sea just north of the capital, and has noticed the changing water levels. In our culture, those who can do more in a family should contribute more than the others - so it's obvious that other countries should do more to help us. For people like Ana Tembe, that help cannot come soon enough. map of Maputo (courtesy of the National Institute for Disaster Management)     * Rotterdam     * Adaptation <http://news.bbc.co.uk/1/hi/world/africa/8366538.stm By Michael Hirst BBC News, Rotterdam Rotterdam skyline *Rotterdam does not feature highly on lists of must-see sites in the Netherlands.* Heavily bombed by the Germans during World War II, Europe's busiest port lacks the rustic charm of Amsterdam. But city authorities are aiming to turn it into an international showcase for water management, making a virtue out of what was once its biggest threat. Although the story of Hans Brinker shoving his finger in the dyke to stop it from bursting is a myth, Dutch expertise in this field is not in doubt. With much of its land mass below sea-level, the country has been battling the sea for centuries, using dykes and windmills to control the flow of water. *Risk remains* Daniel Brakman remembers the last time Dutch sea defences were breached - in 1953. Floating pavilion, illustration courtesy of Rotterdam Climate Proof In pictures: What to do with water? <http://news.bbc.co.uk/2/hi/in_pictures/8362183.stm I was a young boy, I was home with my brother and my sister and there was water around our house as far as the eye could see, says the 63-year-old hairdresser. The storm surge killed nearly 2,000 people and inundated swathes of land. It prompted the Dutch to develop a delta plan which means Rotterdam now lies behind several hundred kilometres of dykes. A network of sluices, locks and barriers give it some of the world's best sea defences, which would only be breached by a one-in-10,000-year storm. But while the impressive Maeslant barrier, for example, could withstand a several-metre surge in water levels, the risk remains that a major flood could breach the defence system, affecting around half the Dutch population. A one-in-10,000-year protection level sounds very good... but it's just statistics, and that event could happen tomorrow, says Piet Dircke, professor of Urban Water Management at Rotterdam University. *Country at risk* Hurricane Katrina - which wreaked havoc on New Orleans in 2005 <http://news.bbc.co.uk/2/hi/in_pictures/8362183.stm - was a clarion call against complacency, says Mr Dircke, who is also director of water programmes with the global engineering firm Arcadis. The Netherlands has established a plan to bolster its flood protection system by making it:     * Bigger, with higher sea barriers     * More natural, through schemes to widen rivers, reinforce the       coastline with sand and start building floating homes     * Smarter, using technology to provide an early warning system and       evacuation plan Rising sea levels are not the only problem facing the country. Increased urbanisation is putting pressure on sewage systems and increasing the risk of flooding, and the country is subsiding at an even faster rate than the sea level is increasing. We're getting more water out of Germany from the river Rhine, more from heaven, water out of the sea and out of the soil, so water's coming from four sides and we have to have answers for all four aspects, says Rotterdam's Vice-Mayor Lucas Bolsius. All of these sources of water will be monitored by a new system, being developed by IBM <http://www.ibm.com/ , to collect and analyse real-time data, in order to evaluate flood threats. For example, there is a plan to install sensors on dykes to raise the alarm when a barrier is about to be breached, allowing the government to give a 24-hour warning of the need to evacuate. *Live laboratory* As it works on these innovations, Rotterdam is essentially developing a live laboratory to put them to the test. MAESLANT STORM SURGE BARRIER The Maeslant barrier, pic courtesy of Dutch Ministry of Transport, Public Works and Water Management Gates are the length, and twice the weight, of the Eifel Tower When closed, 22m-high barrier straddles 300m-wide river Completed in 1997 at cost of 450m euros Expected to close once every 10 years, frequency doubling by 2050 With many modern ships unable to pass through the shallower waters in the city centre, the shipping industry is moving westwards, with its new deep-water port stretching over a distance of 40 km (25 miles) towards the North Sea. This is leaving a 4,000-hectare area around the old docks where government departments are pooling their resources with universities, engineering and IT firms to develop sustainable energy technology. The city plans to halve its carbon emissions by 2025, and to reduce net emissions to zero in due course. On a river-tour, water manager John Jacobs showed off the Research, Design and Manufacturing campus, <http://www.rdmcampus.nl/ a hive of creativity _base_d in one disused shipping wharf. It's an excellent example of how a port city can change its focus to tackle the challenges of climate change, says Mr Jacobs. The site is now home to a clutch of vast greenhouses containing workrooms and lecture theatres where scientists and students work together with businesses and engineers to develop eco-friendly products from hi-tech bicycles to footwear made with sustainable materials. *Adapting to change* Rotterdam's ultimate goal is to make itself climate-proof - able to withstand whatever the weather throws at it - by 2025. In addition to hi-tech water management systems, the city is also exploiting soft technology such as water plazas, green roofs and multi-purpose storage facilities. <http://news.bbc.co.uk/2/hi/in_pictures/8362183.stm Water taxis in Rotterdam Water taxis may one day ply between floating housing developments More ambitiously, it plans to develop a 50-hectare (120-acre) floating housing development, with a neighbourhood of environmentally friendly houseboats. The showcase for this development is a floating pavilion under construction that will be completed in time for the start of the Tour de France in Rotterdam next July. Rotterdam hopes to share its knowledge, exchanging ideas on low-cost methods of flood protection with both developed delta cities and developing countries - like Mozambique - that face a similar threat from water. <http://news.bbc.co.uk/2/hi/africa/8363045.stm The question will be how can you transfer this technology to other areas, how can you make it suitable for countries in other climates and economic situations, says Piet Dircke.     * Adaptation By Kate McGeown in Maputo and Michael Hirst in Rotterdam One of Vasco Mula's dams Vasco Mula knows that his dams are just a temporary solution *Vasco Mula is the leader of a Mozambican community that farms a large area of land where the Limpopo river meets the sea.* The soil has always been good farming land - able to grow rice, sweet potatoes, garlic, onions and many other staple crops. But every year, more and more salt water from the sea is getting into the irrigation channels, affecting the harvest. We mainly grow rice here, and rice needs a lot of water - water that's not salty, Mr Mula said. His solution is to build little dams across the irrigation channels - rudimentary structures made from mud, twigs and bits of sheet _meta_l - to keep the fresh water and sea water apart. The community has asked for more permanent help from the government and foreign aid organisations - but right now they know they can only rely on themselves. Mozambique map The situation is very different in affluent Europe. In the Netherlands, for example, people seem confident the government will help them withstand the effects of climate change. <http://news.bbc.co.uk/2/hi/in_depth/836214.stm I trust the government because the Dutch are the world number one at dealing with water, said Rotterdam restaurant owner Metin Kekeg. Shop worker Jenn Tshau added: In some areas I doubt the safety, but here in Rotterdam I feel safe. Since the deadly Dutch storm surge of 1953, the risk of flooding has been considered a national issue. Citizens do not even need to insure their homes against flooding, as the government is seen as ultimately responsible for their protection. Water management expert Piet Dircke estimates the country's new flood defence system will cost about 1bn euros a year for the next century - but this is still a tiny percentage of Dutch gross domestic product. *Lesson from the floods* It is not that the government in Mozambique is doing nothing. With limited resources, it is slowly starting programmes to adapt to climate change <http://news.bbc.co.uk/2/hi/africa/8363045.stm , and if communities push hard enough, they can sometimes get additional government money for their own projects. Maniquenique school Hundreds of people can crowd onto the roof of the Maniquenique school A good example of what can be achieved if a community works together is the elevated school in the village of Maniquenique, further up the Limpopo river from Vasco Mula's farmland. After the devastating floods that killed more than 700 Mozambicans in 2000, the inhabitants of Maniquenique decided to ensure they never went through such trauma again. With money and help from the local government and UN Habitat, they constructed a building on concrete stilts , which doubles as a school during the dry season and a place of refuge in the event of another flood. Even the roof was designed to hold hundreds of people. Everyone in the community came to help build it, said teacher and local community leader Luisa Paulo Langer, not just the people living near the school - everyone. Versions of this simple design could be used up and down the coast, and in other delta areas, as the effects of climate change start to increase the risk of flooding. Another way people can adapt to the changing environment is to alter the selection of crops they grow. Dam in Rotterdam Dams in the Netherlands are some of the most sophisticated in the world About 70% of Mozambique's population live in rural areas, the vast majority of whom farm the land for a living and are dependent on certain climatic conditions. Some are already finding they need to grow different crops. Mr Mula, for example, can no longer farm garlic and sweet potatoes in certain fields because of the salt. And it is not just rising sea levels that are causing this change. People in southern Mozambique may well suffer increased drought, and some communities are already switching from growing maize to sorghum, which consumes substantially less water. This is not just about what people grow - this will have a profound affect on the culture of the area too, said Professor Antonio Queface, one of the authors of a national report on the impact of climate change. *Forewarned is forearmed* If people are going to adapt to climate change successfully, they need to know what they are up against. Education is completely key, and there's no doubt communities that know what will happen can prepare much better than those that don't, said Professor Rui Brito, an environmental expert at Eduardo Mondlane University in Maputo. Most people in the West have at least a basic knowledge of the impact of global warming. In Mozambique, things are rather different. Vast numbers of people don't know what you're even talking about, said Antonio Reina, the director of Livaningo a local environmental organisation. I actually don't know why the sea is rising. I only know that it is, and the problem seems to be getting worse, said Selva, a 23-year-old man on the beach in Maputo. In many cases - even if people are vaguely aware that something is happening - they are simply too poor to do anything about climate change, or even see the issue as a priority. After all, why worry about something that might happen in a year, or even 10 or 20 years', time when you do not have adequate food and shelter for your family right now? In the words of Professor Brito: The main fight now is still poverty, not climate change.