The existential toll of climate change on wetlands – maybe we should go with the flow.

By David Salt

Every February we’re encouraged to think about wetlands as we celebrate World Wetlands Day. While society has come a long way in changing its mind about the value of wetlands – once they were smelly swamps, now they are precious, life-sustaining ecosystems – these days we’re stuck in a form of denialism about their prospects as climate change radically threatens their very existence.

The sad truth is, climate change modifies water levels, and the best protected wetland in the world ceases to be a wetland without water. Too much water, in the form of rising sea levels, will have the same outcome. If we can’t protect our wetlands in the space they exist today, do we need to make more effort to let our wetlands move with the flow?

Fifty-one years of Ramsar

Fifty-one years ago, on the 2nd of February 1971, one of the world’s most important international environmental conventions came into being with the adoption of the Convention of Wetlands. It’s important because it was the first international treaty for wetland and waterbird conservation, and one of the world’s most enduring and significant international agreements on the environment. It’s been responsible for establishing the world’s largest network of protected areas – being declared a Ramsar Wetland is akin to being listed as a World Heritage area – and the treaty has been used as a basis for other international conservation policies and national wetland laws.

The adoption ceremony for the Convention was held in the Iranian city of Ramsar, on the shores of the Caspian Sea, and most people know this Convention as the Ramsar Convention. To mark the day of the treaty’s creation, the Ramsar Secretariat has promoted the 2nd of February as World Wetlands Day, and it’s been run on this date every year since 1997.

The Ramsar Convention together with World Wetlands Day have transformed the way humans engage with wetlands. They’ve gone from ‘swamps’ only fit for draining and development, to critical land and water scapes that provide humans with a range of valuable ecosystem services in addition to being critical habitat for biodiversity conservation. Wetlands, in all their forms, are now recognised as precious and irreplaceable.

However, our efforts to increase awareness about the state and value of our wetlands have also revealed they are in serious trouble. The Ramsar Secretariat’s Global Wetland Outlook (newly revised this year) tells us that over a third of the planet’s wetlands have been lost since the Convention was enacted. Indeed, wetlands are our most threatened ecosystem, disappearing three times faster than forests. Land-use change is the biggest driver of degradation to inland wetlands since 1970. Agriculture, the most wide-spread form of land-use change, has damaged more than half of the Wetlands of International Importance (often referred to as Ramsar Wetlands). Climate impacts to wetlands are happening faster than anticipated. Rising sea-levels, coral bleaching and changing hydrology are all accelerating, with arctic and montane wetlands most at risk of degradation and loss.

Land locked and lost (or drowned)

And here’s an irony the Treaty’s designers probably never envisaged: The city of Ramsar, the place that gave the treaty its name, is rapidly becoming land locked as the Caspian Sea shrinks under climate change and water extraction. Its surrounding wetlands will be gone within decades.

The Caspian Sea is actually a landlocked lake with a surface that is already around 28 metres below sea level. And it’s dropping by 7 centimetres every year. As temperatures rise with global warming, evaporation will accelerate this decline. The Caspian Sea will be nine to 18 metres lower by the end of the century and lose a quarter of its size. How do you sustain a wetland that can no longer be kept wet? Researchers believe the unfurling crisis will result in an ecocide as devastating as the one in the Aral Sea, a few hundred kilometres to the east.

Falling water levels are challenging many other major landlocked lakes and seas (consider the Aral Sea and Lake Chad) but most coastal wetland systems face the opposite problem – rising sea levels associated with warming oceans, another consequence of climate change. Sea levels are currently rising by between 3-4 mm per year but this is expected to accelerate in the coming decades. This could lead to the submergence of 20–78% of worldwide coastal wetlands by 2100!

Whether water levels are rising, falling or doing major damage through extreme weather events (think of this season’s unprecedented flooding all around the world), the prospects for the planet’s precious wetlands are darkening with every year. World Wetlands Day (and the Ramsar Convention) have played a valuable role in highlighting the importance of these watery ecosystems, as well as identifying wetlands of particular significance; but as climate change bites we need to face the grim reality that changing water levels mean that many, possibly most, wetlands cannot be protected by surrounding them in strong laws, good signage and a more receptive society. The sad truth is that shifting water levels mean many wetlands cannot be protected in their current spaces.

Just as the city Ramsar heralds this grim reality, the history of the Caspian Sea upon which it lies, may hold a possible solution. The Caspian Sea has a history of rises and falls. Around 10,000 years ago the sea was about 100 metres lower. A few thousand years before that it was about 50 metres higher than today’s level. Yet people who lived beside the sea were able to move with the fluctuating sea level. Back then, no large human infrastructure was around to be destroyed, and people moved (adapted) as required. The same applied to animal and plant species. Ecosystems simply moved up and down as the sea level shifted, as they had done over the past 2 million years or so.

In today’s world, with massive city infrastructure and property rights attached to specific locations, moving with a changing water level presents enormous challenges. And yet, doing nothing (ie, not moving) is not an option either. Roughly a tenth of the world’s population and assets are based less than 10 metres above sea level. Sea level rise means land currently home to 300 million people will be vulnerable to annual flooding by 2050.

Water is the messenger

Jay Famiglietti, Executive Director of the Global Institute for Water Security at the University of Saskatchewan, recently observed that “Water is the messenger that delivers the bad news about climate change to your town, to your neighborhood, and to your front door.” Our first response, unfortunately, is usually to deny the message as we have so much invested in ‘sustaining’ the status quo. Economists would say we worry too much protecting ‘sunk investments’.

We’d rather reinforce and armour our shores against the rising tides, than consider moving to adapt to rising (or falling) water levels. Not only is this expensive and fails to address the underlying problem – sea level rise is predicted to accelerate, not stabilise – it makes us more vulnerable to the multiple threats being generated by climate change (eg, more intense storms and extreme rainfall).

In many ways, we’re doing the same with our wetland reserves. We’re managing them for the proximate dangers that threaten their natural values such as guarding against pollution, overexploitation and development. But, as with our cities and towns, we’re ignoring the consequences of changing water levels in a time of climate change. The places where we find wetlands today may not sustain wetlands into the future.

In some cases, wetlands have the capacity to move (migrate) with the water level as it changes. Some research is suggesting that sea levels could rise faster than a wetland’s natural migration rate. Other studies have shown their capacity to move is limited by how land is being used around existing wetlands.

The challenge of sustaining our precious wetlands in a time of climate change and changing water levels is enormous. The first step in meeting this challenge is getting beyond denial. Seas are rising. Lakes in many places are shrinking. We can see it happen, and there is a strong scientific consensus it’s only going to get worse. Given this reality, we need to extend the tool box of policy measures to conserve these vital ecosystems. It’s not enough to increase our protection of existing wetlands. We need to start planning on how we can facilitate their ability to move with changing water levels – to go with the flow.

Research is happening in many places around the world to explore what’s possible. For example, Australian scientists are developing the idea of “rolling covenants” to protect coastal ecosystems in the face of sea-level rise. These are conditions on land titles that permit productive use of land in the short term, while ensuring land use can shift over time to allow for coastal ecosystem migration in the medium to long term.

Of course, such provisions require considerable funding and a change in mindset on what is an appropriate way to use (and set aside future uses) of land. But such change is possible when society gets beyond denying what climate change means and works with the change rather than attempting to control it.

‘Making room’ for water

One of the best examples of this is the response of the Netherlands to the threat of rising sea levels and increased flood risk. The Netherlands is both flat and low lying, and has always been prone to flooding. More than half of the Netherlands is located on flood-prone land. Following two particularly horrifying floods in the 1990s, requiring the evacuation of hundreds of thousands of people, the Netherland’s government adopted a new paradigm in water management.

Rather than building bigger dykes and dams to control the floods, they adopted an approach called making “Room for the Rivers” in which floods were better accommodated by the landscape. Many farms were converted to wetlands (proving a boon for bird life), land around rivers was dedicated to allow for flooding, and cities and towns were adapted to cope with flood waters.

The approach cost billions of dollars, many land holders were required to give up their homes and their farm land, and the whole community needed to change the way they dealt with flooding.

The result? Dutch rivers can now absorb about 25% more water than they could in 1995, and the recent episode of historic floods that devasted parts of Germany, Belgium, France, Luxembourg and Switzerland, left the Netherlands relatively unscathed.

If the Netherlands can make room for their rivers and demonstrate the value of this approach to flood control, what would it take for the world community to ‘make room’ for our wetlands?

This World Wetland Day, we all need to consider how we can better go with the flow.

This blog originally appeared on The Global Water Forum

Banner image: Climate change is moving water levels. Moving water levels means wetlands also need to move. We need to ‘make room’ for our wetlands. (Image by David Salt)

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