The glacier maker

A stream in Nimaling valley, Ladakh.

They call him Ice Man. No, he is not a character of the latest Batman movie, but an Indian engineer whose idea, born in 1987, helps villages in the north of India to guarantee their water supply!

Water for the only harvest of the year

Ladakh is a region of the world located in the Jammu & Kashmir northern state of India. It comprises mainly high altitude desert mountains above 3 000 meters. It is a popular trekking destination for its stunning landscapes.

Almost 80% of the farmers in the region depend on snow and glacier melt water for irrigation and domestic use. The summer-season cultivation is short. It is during April and May that the farmers sow for the only harvest of the year. If it is not sown at this time, the crop cannot be fully maturated, resulting in low yielding crops.

Since winters are getting shorter and warmer, and glaciers are retreating rapidly, less and less water is available, and sometimes at the wrong period. The crops are not as good as in the past, less food is available. Already the entire population of some villages had to leave and migrate because of this change.
 

A successful try

An artificial glacier
(Picture : LNP)

Chewang Norphel was born in Leh, the capital of Ladakh. During 35 years he worked in the region as a civil engineer. In 1987, Chewang decided to help four villages in Shara valley. He says : “At that time the water supply was already a serious problem for four villages since there was only one stream in the valley.”

“I came out with an idea. What if water could be stored during winter so that it is available later during spring? Which practically means building… an artificial glacier! And it worked! We managed to force the creation of a glacier which provided few months after the water that the villages needed.”

A stone structure is built to 

retain the diverted water 

which will accumulate and 

create the artificial glacier.
(Picture : LNP)

Chewang explains how an artificial glacier works : “At the start of winter, water is diverted from a main stream to let it flow onto a sloping hill. Distribution channels are constructed with stones on the hill. Ice retaining walls are built at regular intervals to impede the flow of water and to make shallow pools. This is how a huge quantity of water is kept stored!”

The hill must be located on a shaded area, facing north side, where winter sun is blocked by a ridge or a mountain slope. This will ensure that the accumulated water stock will not melt during the winter. The process of ice formation takes place during the 3 to 4 winter months and as a result a big reserve of ice accumulates on the mountain slope.

(Picture : LNP)

Ice Man concludes : “The artificial glacier starts melting in spring, right in time for first irrigation. After the success of Shara glacier, we have built about 10 more glaciers.”

The brilliant idea of Chewang has changed the life of many. Adaptation to climate change is already a vital necessity in several areas in the world, let’s react all together before adaptation concerns all of us!

Chewang and Carolina at the office of Leh Nutrition Project
where Chewang currently works as Chief Project Officer.

~~~

During these last years, Chewang has received the following awards and honours:

Best Rural Engineer Award from the President of India ;
Rural Engineer Award by Center for Science and Environment, New Delhi ;
Asian Innovative Award of Hong Kong, Far Eastern Economic Review Magazine ;
CNN-IBN ‘Real Hero’ Award, 2008 (a video, here).

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Rains sinking the homes and the economy

Atchara and Carolina

At the end of last year, Thailand experienced the country’s heaviest flooding in 50 years. The flood claimed 800 lives and paralysed Thailand for long weeks.

Atchara Suriya works in a tourism agency in Bangkok. We had the chance to meet her at the end of May and, in the middle of a conversation, we started to talk about the floods of 2011. This is what she told us. 

Heavy monsoon rainfalls 

“I am originally from the town of Pathum Thani, north of the capital Bangkok. My region has been one of the most affected by the floods. These last months have been very special for us”. Atchara explains: “The floods resulted from strong rainfalls. Depending on the place, the water went up slowly or very suddenly. At one of my friend’s, it took less than 12 hours for the water to go up to 1 meter.”

“I got only 50 cm in my home. My family and I did not leave. My parents did not want to because of the belongings and because of… our two dogs! So, like lots of others, we decided to stay, and spent our time on the 2^nd floor or on the roof of the house. I remember that preventing the water to come from the outside was useless since the toilets or the drainage would overflow. The old people would not stop saying : this never happened before, this never happened before!”

   Pathum Thani is some kilometres 

far from Bangkok. The ancient capital Ayutthaya is a little bit further North.

 The whole region on this map particularly suffered from the floods. It is here that lots of automotive and electronics plants operate.

“Of course the life in the village changed. Everything stopped. Everything turned to be more expensive. During this exceptional situation we could see lots of positive behaviour. For instance those who had a car would share it with others. People who had never talked to each other would start to do it. The village got organized differently”. About the action from the authorities, Atchara says : “We could see that we had no experience of flood. There was such a lack of organization from both the people and the authorities.”

Crippled tourism and industry 

When we were in the ancient 

capital Ayutthaya, we could 

observe the marks 

left by the water…

“The whole region kind of stopped. Firstly the tourism was impacted. The ancient capital Ayutthaya is close to my town, a little bit north. The historical heritage there was at risk and much less tourists came during the flooding months.

Secondly, the region where I live is an industrial area, there are lots of factories around. The floods stopped the activity for most of them. Lots of small companies basically closed as the losses were too big. In some Japanese companies, the Thai people had to choose between moving to Japan and work there for a certain period… or losing their job. A cousin of mine stopped working for one month. She stayed at home, with no revenue, in 2 meters high waters.”

Atchara concludes : “I hope the authorities will learn from what happened, I hope we can be better organized to face floods. Nature is changing. But nature rules our life so we must pay attention to it. We are responsible for it!” 

An economy hit for a long time 

Climate change includes changes in precipitation around the world. The Intergovernmental Panel on Climate Change (IPCC) declares the following: “Anthropogenic influences have contributed to intensification of extreme precipitation at the global scale. It is likely that the frequency of heavy precipitation or the proportion of total rainfall from heavy falls will increase in the 21st century over many areas of the globe. This is particularly the case in the high latitudes and tropical regions, and in winter in the northern mid-latitudes.”

The 2011 heavy rainfalls and the resulting flood had a huge impact on Thailand’s economy. The country’s growth in 2011 was only 0,1% ; much less compared to 2010 growth of 7,8%.
 
More than 10 000 factories were forced to close and to lay off more than 350 000 workers while production was suspended. Japan economy shrank 2,3% in the fourth quarter 2011 partly due to the flooding that disrupted production at leading manufacturers such as Sony and Honda. The worldwide supply chain of hard disk drives – used in computers – was disrupted and the prices rose up. The manufacturer Western Digital announced recently that the situation will not come back to normal before… 2013.

Honda cars under water - Ayutthaya region

Photo : Getty Images

 ~~~

 

In Asia and the Pacific, 42 million people were displaced by environmental disasters between beginning 2010 and beginning 2012 (Asian Development Bank)

U.S. insured losses from weather disasters have soared from an average of about $3 billion a year in the 1980s to about $20 billion a year in the last decade, even after adjusting for inflation (Swiss Re) 

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Winds and chaos

Yesterday, in a kitchen in Washington D.C. :

  - Michele : “My Dear, do you know that last March has been the hottest month of March in the U.S. since 1895 ?! I do not like these heat waves. Can’t the scientists predict them?”

  - Barack : “Oh Dear, climate is complicated, it is very difficult to predict. And concerning the heat waves, unfortunately global warming will mean more of them!…”

Chaos in the air 

For the scientists dealing with climate change, the forecast of the climate in the next decades is a key item. Models build these predictions. They show trends however no one can declare they are perfectly accurate. Why? Because the climate is an extremely complex system and humans have been studying it for only few decades.

We met Christophe in Nouméa 

on the 16^th of April. In the past 

Christophe worked in the 

United States and Ivory Coast.

“The weather here in the Pacific Ocean is even less predictable than in the Atlantic Ocean for instance”, says Christopke Menkes. We met Christophe Menkes in Nouméa, New Caledonia, at the Institute of Research for Development (Institut de Recherche pour le Développement, IRD) which is a French governmental organization dedicated to research, outside of metropolitan France. Christophe is an expert in oceanology and focuses especially on cyclones, environmental impacts on tuna, and climate effects on Dengue spreading.

Christophe explains : “When dealing with climate predictions, there is a part of variability that cannot be reduced. The chaos theory explains this : many conditions influence the climate and very slight changes of these conditions can totally modify the consequences.” Maybe you have heard about the butterfly effect? 'A butterfly wing flapping in Japan might be the origin of a cyclone in the United States!'

From winds to cyclones 

Christophe adds : “For instance, about cyclones, specific winds of West Africa are always at the origin of the Atlantic cyclones. It is what we call a forcing input. In South West Pacific, the conditions are more complex and more random”.

The tropical cyclones, between 1945 and 2006 -
The area in South West Pacific where the cyclones are generated extends from the Solomon Islands to Tonga. New Caledonia is located in the middle of this cyclonic region.

“Concerning the cyclonic activity in the South West Pacific region, studies say that global warming will not necessarily mean an increase in numbers of cyclones. Regarding their intensity, only two studies have been published so far and they predict that the cyclones will be more intense in this region. The question should be more investigated to give solid conclusions”, says Christophe.

“Regarding the Central Pacific, things are clearer. The phenomenon El Niño has a direct impact on the generation of cyclones.” The El Niño episodes are defined as warmer than normal sea-surface temperatures in the tropical Pacific Ocean. “The more El Niño occurs, the more cyclones will emerge ; and the studies show that climate change is the origin of more and more periods of El Niño.”

Irene, Katrina, Rita… nice names which worry North East America

Concerning the Atlantic, there is observational evidence of an increase in intense tropical cyclone activity in the North Atlantic since about 1970. “In some cases natural variability of the climate can result in an extreme event being more intense on a long period. However in the North Atlantic the recent change is a consequence of human activity,” says Christophe.

The cyclone (or hurricane) Katrina of 2005 was one of the most destructive and expensive natural disaster in U.S. history. It claimed 1 800 lives and caused 134 billion dollars in damage (U.S. Global Change Research Program, 2009). We also remember that last year Irene forced New York City to stand still during some days and be partially evacuated. The Big Apple will probably experience these circumstances again in the future.

 

Land lost during 2005 Hurricanes - 

In 2005, in the United States, 560 km² of land and wetlands were lost to open water during hurricanes Rita and Katrina. The photos and maps show the Chandeleur Islands, east of New Orleans, before and after the 2005 hurricanes ; 85 percent of the islands’ above-water land mass was eliminated (U.S. Global Change Research Program, 2009).

At end of March, the Intergovernmental Panel on Climate Change (IPCC) published a special report about extreme events, called Managing the Risks of Extreme Events and Disasters to Advance Climate Change Adaptation. The report assesses the evidence that climate change has led to changes in climate extremes – cyclones, droughts, floods, heat waves - and the extent to which policies to avoid these prepare for, respond to and recover from the risks of disaster can reduce the impact of such events. Regarding cyclones, the conclusions are the following : “first, it is likely that the global frequency of tropical cyclones will either decrease or remain essentially unchanged. Second, average tropical cyclone maximum wind speed is likely to increase, although increases may not occur in all ocean basins.”

~~~

Presentation video of the special report by the IPCC. The report can be downloaded here.

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French Polynesia looking ahead

We met Jacky Bryant on the 

21st of February at the 

Ministry of Environment, 

in Papeete, Tahiti island.

“An opportunity for humankind to rethink”. These words from Jacky Bryant, Minister of Environment of French Polynesia, show a pretty distinctive idea about climate change. And we liked to hear this from someone with such responsibilities!

A Plan on Climate Change, for the whole society to think sustainable

As with most of the countries in the Pacific, the overseas country of the French Republic (Pays d'Outre-Mer) has a high vulnerability with regard to climate change. French Polynesia is composed of several archipelagos, with small and mostly low altitude islands, and where sea level rise and cyclones are ones of the greatest threats.

When we met Jacky Bryant at end of February, he and his team were preparing a significant two-months task : several workshops taking place during March and April, with the final objective to draft a Strategic Plan on Climate Change (Plan Climat Stratégique). Each workshop deals with a specific sector and gathers the corresponding local socio-economic actors : transport, urbanism, energy, ecosystems, etc. The main purpose of the Strategic Plan is to issue recommendations and guidelines for a global sustainable development of the country. It will be adopted as a national development policy and taken into account on other government programs.

French Polynesia is made up of 5 groups of islands : the Society Islands, the Tuamotu Islands, the Gambier Islands, the Marquesas Islands and the Austral Islands.
(Picture : GNU Free Documentation License)

Prized seas

When we asked the Minister how French Polynesia makes its voice heard during international discussions about climate change, he replied : “French Polynesia lies on a 5 million square kilometers maritime surface. This is larger than the whole European Union. The natural resources are numerous, but here you will have to look below the ocean to see them! For instance, the undersea grounds contain lots of rare earths, which are nowadays the subjects of strong economic and strategic interests.”

Rare earth properties and uses table. 

(Picture : Geoscience Australia)

The rare earths contain the elements required in the manufacturing of our mobiles phones, TVs, other electronic equipments and also green-energy technologies. Today China produces more than 90 per cent of the world's supply but takes advantage of this position. Recently European Union, USA and Japan have launched a joint complaint against China before the World Trade Organization, denouncing China's limits on its exports of rare earth metals.

“Another example is the fish resources”, Jacky Bryant adds. “There is an area north of our Tuamotu archipelago where tuna reproduce. The huge quantities of tuna in this area make it very valuable and fishermen from all over the world would like to come and fish there.

We do not mean that we want these resources to be exploited. We are just saying that French Polynesia is not only some ‘rocks floating in the middle of the Pacific’. If these resources are to be exploited one day, it must be in a very sustainable way.”

Jacky Bryant comments : “Chinese and Russians for instance understood the values of the Pacific waters. This is why they have started to invest in some countries, without any compensation, building stadiums for free for example. Long term investments to ensure them a position in the Pacific…”

Climate change and… education

Drivers of change in small islands and 

the implications for island condition 

and well-being under no adaptation 

and the near-term and mid-term 

implementation of adaptation. 

[IPCC 2007 Report, adapted from 

Harvey et al. (2004)]

 “We know that climate change will result in several kinds of difficulties in the future. And we try to get ready for that”, says the Minister. “For instance, we have in mind which islands could be the destination of a possible migration of people, due to sea level rise. This destination would be the Marquesas Islands, North East of French Polynesia. These islands have higher altitude lands and lots of these lands still belong to the State.”

Jacky Bryant adds : “I am convinced that the future changes represent also an opportunity to correct and to re-think. Lots of components of our society have to be rethought. Sustainable development must be part of all actions and changes should also be the occasion to improve. Let’s take the example of tourism in French Polynesia : today we offer mainly seaside tourism, tomorrow we should also promote a cultural tourism”.

This temple, called marae, is part
of the archeological heritage
of the Moorea island.
Surprisingly it is located in the
middle of a private property,
which was bought some years ago
by an American.

The tourism is the first economic sector of the country and represents around 25% of local gross domestic product (IEOM, 2008). Nevertheless French Polynesia is mainly a seaside tourism destination. It is often associated to white sand beaches and turquoise waters! The Minister explains : “There is a strong archeological heritage to protect and promote. This is why I am in favor of creating a university diploma in archeology, which for the moment does not exist here. Our cultural and heritage sites are located in coastal areas. On the one side, climate change will have an impact on the seaside tourism and on the other side, it will imply adapting the coastal infrastructures : French Polynesia needs qualified people to control and go along with it!”

~~~

In a previous article, we mentioned that Maldives is trying to buy land in Sri Lanka and India as anticipation to possible relocation of the population due to sea level rise. Recently Anote Tong, President of the Kiribati in Central Pacific, recognized that there is an ongoing discussion with the government of Fiji, in order to buy land there. Kiribati has already started to see its coasts taken by the waters, mainly due to sea level rise and erosion, and has no other choice but to prepare a migration of its entire population, 113 000 people.

 ~~~

Journalists followed us while we met Jacky Bryant end of February. This is the news report, by the French Polynesia TV channel TNTV.

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Planet Rapa Nui

This is the story of a prosperous civilization which consumed without control the resources of their place, to such a point that these resources nearly disappeared, conflicts between people popped up and the civilization lost its greatness. Are we talking about human civilization on Earth today? Near future will tell us how things will evolve, but let’s see here what happened to the inhabitants of Easter Island, the small island in the Pacific, in the middle of last millennium.

Symbolic Moais

Rapa Nui is the name of Easter Island in local Polynesian language. Jacob Roggeveen (1659-1729) reached the island in 1722, the day of Easter - thus the name - and while exploring the island, the Dutch navigator could observe what is today the symbol of the island : the moais. The moais are huge megalithic figures representing the ancestors of the island clans. They were carved from the volcanic rock of the island, and then transported to their final place somewhere on the coast. The erected ones can be up to 10 meters high and weight 86 tons. They all look towards inside the island.

The first residents settled on the island in a period that is not clearly defined, due to few data available ; this period is between 400 AD and 700 AD. The explorers came from west, from the Marquesas islands in nowadays French Polynesia. At that time the island was the home of one of the highest palm trees on Earth and of several bird species. From then, the population adapted to the environment and rose slowly. Between 900 and 1300 the human population of the prosperous society started to increase more rapidly, reaching possibly 15 000 inhabitants. Also during this period more and more moais were erected by the different clans of the island.

Easter Island is a volcanic island. It lies 3 500km west of continental Chile

From around 1300 the Rapa Nui people started to face an issue : the number of trees, which represented a key resource, turned to be insufficient! Three main causes explain this slow disappearance of the trees.

Tree lessons

Firstly, the islanders had developed much technology - not only related to the wood - and trees were used a lot during everyday life by the growing population. They were used to build boats or to transport the moais for instance. Actually the moais turned to be the subject of a competition between the clans. Higher and higher, bigger and bigger. More and more wood was cut to displace the moais. The problem is that the Polynesian cut the trees without control and did not replant. They over-consumed the resource and forgot about the day after. This can be lesson number one : the resources are rarely unlimited, and today human being is over-consuming the natural resources of the planet.

The scientists or the historians are not certain about which technology was used to transport the moais. Nevertheless, whatever the technology, wood and cordage was employed. (Pictures : P. Pavel)

Secondly, a forest can be fragile. As more and more trees were cut, the whole ecosystem became poorer to such a point that the forest collapsed by itself. This is close to the concept of tipping point that we mentioned in a previous article. The Rapa Nui people did not cut the last tree! The forest turned to be more and more fragile, damaging also the soils and the fauna. This can be a lesson number two : nature is fragile, humankind should stop to overuse and must anticipate. Scientists talk about a risk of runaway climate change : the situation could reach a point from where changes will accelerate and will be irreversible.

Thirdly, a proliferation of rats could also explain the loss of the trees. The rats eating the seeds and the roots prevented the proper development of the forest. This can also be a lesson : the invasive species can be a threat for the local environment. The recent abrupt climate changes on Earth promote these invasions. Large flooding, droughts or forest fires allow new species to settle and potentially disturb. For instance global warming could bring malaria back in Europe in the next decades.

The end of an era

During 17th century, the consequences of the loss of the trees became critical on Easter Island. The islanders adapted to it but the trees were vital to the society. Population went down. Famine came, but also cannibalism. Conflicts between the clans appeared and some historians even talk about wars. The clans started to pull down the moais of the adverse clans and there is actually not a single moai that was not brought down. Still today lots of the moais of Easter Island are down. The Rapa Nui people carved around 900 moais but less than 300 were transported to their final place on the coast. Most probably due to the lack of wood.

Some moai have a pukao on their heads. The pukao is a kind of hat and is made
of a specific volcanic rock. On the right, a pukao in front of fallen moais.

“Easter Island is a laboratory where you can observe how men used, destroyed and adapted!” This is one of the first things Sonia Haoa told us. Sonia has been an archeologist working on Easter Island for 35 years and particularly she has an excellent knowledge about the use of the stones by the Rapa Nui people. 

“I do not like to say that what happened was a brutal collapse, because it took time for the forest to disappear. It was more like a slow and tough adaptation to a poorer environment… the end of an era for the Rapa Nui people”, says Sonia. “The islanders were isolated from the rest of the world. This island was their small planet!" Sonia adds : "they have always showed a great capacity of adaptation to the fragile environment of the island. For instance after the loss of the forest, they understood that they had to pay even more attention to their soils, and they turned to be remarkable managers of stone gardens. Stone was available in great quantities on the island, and they successfully used it in order to improve yield.”

 



In the garden of her office Sonia replanted Toromiro which is an endemic species to Easter Island. The plant once disappeared entirely from the island but was kept in a botanical garden in Sweden.
We met Sonia on February the 15^th.

The other Earth… that we do not have

“Today men lost the contact with the nature and the resources. So many people do not know where the food or the goods they buy come from. People lost their ability to observe”, Sonia adds.

  

Nowadays human society consumes lots of natural resources without control and without anticipation. The experience of Rapa Nui can be related to the current excessive deforestations that occur all around the world, releasing huge quantities of carbon dioxide and impacting the water availability for instance. We can also mention the example of bluefin tuna overfishing in the Mediterranean Sea. So many bluefin tuna is caught that it could disappear from this sea in the next years. 

Sonia comments : “how is it that humankind does not react though we are aware of the ongoing change and the resulting risks? Today information is available, technology is also available!” According to the World Wildlife Fund (WWF), if human beings do not change their relation to the natural resources, humanity will need a second planet Earth by 2030. Another planet that we do not have.

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Glaciers at your feet

© RTimages - Fotolia.com

Piscola is one of the national drinks in Chile. It is a mix of the aromatic spirit Pisco and cola! Now let’s have an experiment : fill a glass with ice cubes, add Pisco and cola, up to the top of the glass and wait one hour. Observe : the ice disappeared however the glass has not overflew. Why? Because the volume of ice water is quite the same as liquid water.

So does it mean that sea level is not rising because of melting Arctic, which is a big ice cube floating on the Arctic ocean? Basically yes. The contribution from its melting is minor to sea level rise.

However reducing ice masses which are on land do impact sea level…

The glaciers as indicators

Tongue of the glacier Viedma, one of the
biggest glaciers in Argentinian Patagonia.

Glaciers provide among the most visible indications of the effects of climate change. The volume of a glacier is clearly determined by the climate. As the local temperatures increase, the volume of the glacier decreases.

All around the world, the retreat of the glaciers has accelerated during the last decades. Strongest mass losses are observed in Patagonia, Alaska, northwest USA and southwest Canada. In France, half the glaciers of Pyrénées Mountains disappeared during 20th century. In 1930 Colombia had 14 glaciers ; today 8 of them have disappeared. Actually most inter-tropical glaciers are very likely to disappear by 2025 (Ramírez et al., 2001).

 

 A 30 meters high block of ice 

detaches from the glacier 

Perito Moreno (Argentinian Patagonia).
In few words, a glacier retreats when
more ice is lost at the front of the glacier than created at the top. 

Southern Patagonian icefield, one of the largest fields of ice on the planet

When we met Dr. Juan Carlos Aravena, he was about to take an airplane to Antarctica, the day after. Juan Carlos works at the institute CEQUA (Centro de Estudios del Cuaternario), as researcher in glaciology and paleoecology. The institute is a governmental research office, dedicated to study environment evolution in the southern part of South America and in Antarctica.

We met Juan Carlos Aravena on February the 1st
at CEQUA office, in Punta Arenas, Chilean Patagonia.

Click to enlarge
(Picture : Rivera et al., 2012)

Juan Carlos explains : “the Southern Patagonian icefield is one the biggest ice masses on Earth, after Antarctica and Greenland". As an example he adds : “the glacier Jorge Montt, located in Southern Patagonian icefield, has shown a dramatic retreat during the last century. It is one of the glaciers that is the most studied in the region. During 2011 the Chilean Centro de Estudios Cientificos (CECS) installed a camera there taking 6 pictures a day, and from to time to time a scan of the glacier is performed with laser, from a plane”. The following picture shows the evolution of the front of the glacier, since 1898.

Stored before on land, going down to the sea…

The Southern Patagonian icefield
Enlarge (Google Maps)

There are several consequences to the volume decreasing of the glaciers. One of them is the water storage and supply – we talked about water availability in a previous article. “Another key consequence is the contribution to sea level rise”, says Juan Carlos. Patagonian icefields are considered to be amongst the glaciated areas which have contributed the largest proportion of melt water to sea level rise in the second part of the 20th century (Rignot et al., 2003).

Two main factors contribute to observed sea level rise. The first is thermal expansion : as ocean water warms, it expands. The second is from the contribution of ice based on land, due to increased melting. And the major store of water on land is found in Antarctica, Greenland and glaciers.

Between 1930 and 2010, a sea level rise of 18 cm was observed, and the rate of rise has clearly been higher compared to before 1850. According to the 2007 report of the Intergovernmental Panel on Climate Change (IPCC), the sea level rise could be up to 59cm by the end of 21st century. However less conservative recent studies bring more worrying conclusions : 80cm according to W.T. Pfeffer for instance (Pfeffer et al., 2008).

Sea level in the past and as projected for the future.
Over many centuries, sea level could rise by several meters. (IPCC, 2007)

Maldives buying new land

As the oceans rise, low-lying coastal areas will disappear and flooding of these areas will become more common. Loss of land and flooding will have substantial impact on local wildlife, and on humans of course : migrations of populations, social impacts, effects on health, agriculture, tourism for instance. 

More than half of the world's population currently lives in a coastal region. The delta regions are particularly vulnerable. Only 50 cm sea level rise by 2100 will hit one in ten humans around the world. China, USA, India, Bangladesh and Japan will be ones of the most concerned countries (McGranahan et al.,2007).

Relative vulnerability of coastal deltas as shown by the
indicative population potentially displaced by current sea-level trends to 2050 :

Extreme =>1 million ; High = 1 million to 50 000; Medium = 50 000 to 5 000

(Ericson et al., 2006)

As small Pacific Islands are the subject of much concern in view of their vulnerability to sea level rise, several archipelagos - like Tuvalu - have started to be very active these last years in order to warn the international community. 

In Maldives, the highest point of the country is at 3 meters above sea level. End of 2008, one of the first decisions of recently elected President Mohamed Nasheed was to create a sovereign fund with the purpose of adapting to climate change. The fund is supplied from taxes on tourism benefits. Part of it is used to buy land in Sri Lanka and India as anticipation to possible migration of population…

 

Few meters 

and Manhattan would not look the same!
New York City will adapt probably by building walls and dikes.
(Picture : Heidi Cullen)

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