Saltwater poisoning threatens Ghana

Saltwater poisoning threatens Ghana
How is sea level rise poisoning Ghana?

Written by Will

Popular images of sea level change are flooded houses, displaced people and eroded landscapes. In Western Ghana, a sinister new picture is emerging: salt water poisoning. Rising sea levels have polluted the water sources of thousands of inhabitants, infecting their drinking water and creating an unprecedented rise in salt-related health problems.

The head of water quality at the Ghana Water Company has admitted providing drinking water with almost twice the recommended salt levels, whilst the medical director of the regional hospital has reported a 70% increase in strokes, hypertension and heart problems.

Largely ignored in the Ghanaian press, this is a candid portrait of environmental abuse and political mismanagement set to mushroom if current climatic trends continue.

A town on the edge

The focus of the problem is Ada, a town of 20 000 people perched on the estuary of the Volta river. Throughout history the river has provided for and protected the people. Its seasonal floods replenished the floodplain and its powerful flow prevented sea water from travelling up the estuary.

However in the 1950s, the Volta underwent a profound change when the Akosombo dam was constructed. Much of the river’s drainage basin was flooded to create Lake Volta and the flow of water became controlled by the corporate priorities of the Ghana Water Company. Suddenly Ada’s umbilical chord to the interior was cut.

Over the last fifty years, mismanagement of this river system has caused a reduction in water reaching Ada, allowing sea water to encroach upstream and pollute the purification plants supplying the town’s fresh water. Writing in 2007, Dr Philip Narh of Dangme East District Hospital warned that if this problem was left unchecked, it could soon affect the whole 130 000 inhabitants of the South Tongu district. The situation has been created by three major environmental changes.

Rampant deforestation

Thick forest once covered northern Ghana, stretching from the Togo border to Tamale. Rampant deforestation by farmers and charcoal burners has left much of the land barren. The impact on the Volta drainage system has been profound. “Deforestation has completely removed the canopy layer. This layer slowed the rate of run off and supplied the spring source” says Evans Balaara, head of water quality at the Ghana Water Company. “Evaporation rates have also increased as there is no vegetation to provide shade. As a result far less water is now reaching the lake in a normal year than when I was young.” Increasingly erratic rainfall patterns (drought 2007-08, severe flooding 2009) have also added to the problem and in 2006 the only dam in the Damongo (northern) region had to be shut down when its lake dried up. With less water reaching the lake, the ball is set rolling for major problems downstream.

Rising urbanisation

Accra is the 32nd fastest growing city in the world, expanding at a rate of 3% per year. Rural-urban migration - particularly from the northern regions - has been a catalyst for this growth. This has put huge pressure on the urban infrastructure. “The infrastructure cannot keep pace with this increase” says Mr Balaara. “At the moment Ghana Water Company cannot meet the demand from the city. We have to do expansion, but the expansion money is not available yet.” The problem does not lie in the amount of water available, but in the piping and purification system. The pipes are too narrow and the treatment plants too small to process the millions of gallons of water used by the city every day.

Looking to the future Mr Balaara says that the government’s priority is to increase extraction from the lake by building new plants and installing wider pipes. The knock on effect of this is a further reduction in the amount of water trickling down to Ada. Combining this with reduced water inputs, the town’s future looks increasingly bleak.

The rising tide

With the supply of fresh water reaching Ada decreasing, salt water has been able to encroach further upstream. This has been magnified by high spring tides, whose waters have reached Ghana Water Company’s purification plant at Ada. “we have results from Ada when there is a spring tide. The salt levels get up to 350mg per litre, 150mg in excess of our limit of 200mg per litre.” The medical consequences of this have been dramatic. Dr Philip Narh confirmed that a higher number of deaths in the area are caused by hypertension and other heart related diseases. “2.7% of Ada residents are suffering from chronic heart related diseases and this will increase dramatically in the future.”

What is the government planning to do about this? Nothing.

Our hands are tied

Ghana Water Company has no solution to this problem. There are no facilities for desalinising contaminated water at Ada. Replacing the current purification plant with a desalinisation plant is “too capital intensive” to merit consideration. “Our only option is to shut the water purification plant down. But we have no back up supply.”

If the purification plant is shut down, then residents will be forced to use hand-dug wells for their water. These are found further downstream from the purification plant and Ghana water “does not monitor the quality of these sources.” Ada it seems is to be sacrificed.

When you frame this within climate scientists predictions of a one metre sea level rise in the next 100 years the future looks grim. Mr Balaara conceded “If sea level change happens, things will become much worse and we are likely to lose Ada. The buildings will go and the whole land will go. At the moment we don’t have the money to do anything about this.”

The circle of life

Whilst it is easy to criticise the government in its handling of the situation, finding a longer-term solution remains a challenge. An obvious stop gap is to relocate the purification plant further upstream. However this only buys time.

As long as the demand for water from Accra keeps growing Ada’s future remains bleak. The challenge is to find a way to increase the flow of water into the lake and reduce the rampant rate of rural-urban migration to Accra. Putting it another way, to manage the remaining forest (and plant new forest) in a sustainable manner and increase rural capacity to prevent people leaving for the cities.

The options here are much wider. Possible REDD funding could provide an incentive for forest conservation (see Tim’s case study here), whilst a number of other West African countries have small scale projects that increase rural capacity without endangering local resources. One of these is run by Environmental Foundation for Africa, focussing on sustainable forest management. Renewable forest products – bamboo, raffia, cane – are harvested to construct furniture and baskets that are be sold at local market, whilst the hardwoods and canopy layer remain untouched. Sustainability is a vital element to prevent the exhaustion of opportunities that often leads to rural-urban migration.

The fate of Lot’s wife

The story of Ada is a depressingly familiar tale of environmental mismanagement, whose innocent victims are found hundreds of miles from the cause of the problem and whose culprits act out of ignorance or greed. If nobody confronts this then Ada will be swallowed by the sea. But when the first buildings tumble into the ocean, they will tumble on a land that has been desertified by the salt. Spring tides and storm surges will have forced salt water further up the Volta estuary. The medical bills at Dangme district hospital will have climbed and life expectancy will have plummeted. Fields will have been sterilised by high salinity irrigation water and livestock killed off by contaminated drinking water. The population will have either perished or migrated to Accra, perpetuating the vicious cycle that underlies this problem. Like the biblical tale of Lot’s wife, if we fail to heed the warnings of mightier forces, all will soon be turned to salt.

In Ada, sea level did not begin with beach erosion or flooding, it began when the first person turned on their tap to taste the salty solution infecting their waterways.

Dry Regions Becoming Drier: Ocean Salinities Show an Intensified Water Cycle

ScienceDaily (Apr. 18, 2010) — The stronger water cycle means arid regions have become drier and high rainfall regions wetter as atmospheric temperature increases.

The study, co-authored by CSIRO scientists Paul Durack and Dr Susan Wijffels, shows the surface ocean beneath rainfall-dominated regions has freshened, whereas ocean regions dominated by evaporation are saltier. The paper also confirms that surface warming of the world's oceans over the past 50 years has penetrated into the oceans' interior changing deep-ocean salinity patterns.

"This is further confirmation from the global ocean that the Earth's water cycle has accelerated," says Mr Durack -- a PhD student at the joint CSIRO/University of Tasmania, Quantitative Marine Science program.

"These broad-scale patterns of change are qualitatively consistent with simulations reported by the Intergovernmental Panel on Climate Change (IPCC).

"While such changes in salinity would be expected at the ocean surface (where about 80 per cent of surface water exchange occurs), sub-surface measurements indicate much broader, warming-driven changes are extending into the deep ocean," Mr Durack said.

The study finds a clear link between salinity changes at the surface driven by ocean warming and changes in the ocean subsurface which follow the trajectories along which surface water travels into the ocean interior.

The ocean's average surface temperature has risen around 0.4ºC since 1950. As the near surface atmosphere warms it can evaporate more water from the surface ocean and move it to new regions to release it as rain and snow. Salinity patterns reflect the contrasts between ocean regions where the oceans lose water to the atmosphere and the others where it is re-deposited on the surface as salt-free rainwater.

"Observations of rainfall and evaporation over the oceans in the 20th century are very scarce. These new estimates of ocean salinity changes provide a rigorous benchmark to better validate global climate models and start to narrow the wide uncertainties associated with water cycle changes and oceanic processes both in the past and the future -- we can use ocean salinity changes as a rain-gauge," Mr Durack said.

Based on historical records and data provided by the Argo Program's world-wide network of ocean profilers -- robotic submersible buoys which record and report ocean salinity levels and temperatures to depths of two kilometres -- the research was conducted by CSIRO's Wealth from Oceans Flagship and partially funded by the Australian Climate Change Science Program. Australia's Integrated Marine Observing System is a significant contributor to the global Argo Program.

Geologist Connects Regular Changes of Earth's Orbital Cycle to Changes in Climate

In an analysis of the past 1.2 million years, UC Santa Barbara geologist Lorraine Lisiecki discovered a pattern that connects the regular changes of Earth's orbital cycle to changes in Earth's climate.

The finding is reported in the scientific journal Nature Geoscience.

Lisiecki performed her analysis of climate by examining ocean sediment cores. These cores come from 57 locations around the world. By analyzing sediments, scientists are able to chart Earth's climate for millions of years in the past. Lisiecki's contribution is the linking of the climate record to the history of Earth's orbit.

It is known that Earth's orbit around the sun changes shape every 100,000 years. The orbit becomes either more round or more elliptical at these intervals. The shape of the orbit is known as its "eccentricity." A related aspect is the 41,000-year cycle in the tilt of Earth's axis.

Glaciation of Earth also occurs every 100,000 years. Lisiecki found that the timing of changes in climate and eccentricity coincided. "The clear correlation between the timing of the change in orbit and the change in the Earth's climate is strong evidence of a link between the two," said Lisiecki. "It is unlikely that these events would not be related to one another."

Besides finding a link between change in the shape of the orbit and the onset of glaciation, Lisiecki found a surprising correlation. She discovered that the largest glacial cycles occurred during the weakest changes in the eccentricity of Earth's orbit -- and vice versa. She found that the stronger changes in Earth's orbit correlated to weaker changes in climate. "This may mean that the Earth's climate has internal instability in addition to sensitivity to changes in the orbit," said Lisiecki.

She concludes that the pattern of climate change over the past million years likely involves complicated interactions between different parts of the climate system, as well as three different orbital systems. The first two orbital systems are the orbit's eccentricity, and tilt. The third is "precession," or a change in the orientation of the rotation axis.


Story Source:

Adapted from materials provided by University of California - Santa Barbara.

Journal Reference:

1. Lorraine E. Lisiecki. Links between eccentricity forcing and the 100,000-year glacial cycle. Nature Geoscience, 2010; DOI: 10.1038/ngeo828

Sea Level Rise Of One Meter Within 100 Years

Sea Level Rise Of One Meter Within 100 Years

ScienceDaily (Jan. 11, 2009) — New research indicates that the ocean could rise in the next 100 years to a meter higher than the current sea level – which is three times higher than predictions from the UN's Intergovernmental Panel on Climate Change, IPCC.

The groundbreaking new results from an international collaboration between researchers from the Niels Bohr Institute at the University of Copenhagen, England and Finland are published in the scientific journal Climate Dynamics.

According to the UN's Intergovernmental Panel on Climate Change the global climate in the coming century will be 2-4 degrees warmer than today, but the ocean is much slower to warm up than the air and the large ice sheets on Greenland and Antarctica are also slower to melt. The great uncertainty in the calculation of the future rise in the sea level lies in the uncertainty over how quickly the ice sheets on land will melt and flow out to sea. The model predictions of the melting of the ice sheets are the basis for the Intergovernmental Panel on Climate Change's predictions for the rise in sea level are not capable of showing the rapid changes observed in recent years. The new research has therefore taken a different approach.

Looking at the direct correlation

"Instead of making calculations based on what one believes will happen with the melting of the ice sheets we have made calculations based on what has actually happened in the past. We have looked at the direct relationship between the global temperature and the sea level 2000 years into the past", explains Aslak Grinsted, who is a geophysicist at the Centre for Ice and Climate at the Niels Bohr Institute at the University of Copenhagen.

With the help of annual growth rings of trees and analysis from ice core borings researchers have been able to calculate the temperature for the global climate 2000 years back in time. For around 300 years the sea level has been closely observed in several places around the world and in addition to that there is historical knowledge of the sea level of the past in different places in the world.

By linking the two sets of information together Aslak Grinsted could see the relationship between temperature and sea level. For example, in the Middle Ages around 12th century there was a warm period where the sea level was approximately 20 cm higher than today and in the 18th century there was the 'little ice age', where the sea level was approximately 25 cm lower than it is today.

A rise in sea level in the future as in the past

Assuming that the climate in the coming century will be three degrees warmer, the new model predictions indicate that the ocean will rise between 0,9 and 1,3 meters. To rise so much so quickly means that the ice sheets will melt much faster than previously believed. But it has already been observed that the ice sheets react quicker to increases in temperature than experts thought just a few years ago. And studies from the ice age show that ice sheets can melt quickly. When the ice age ended 11.700 years ago, the ice sheets melted so quickly that sea level rose 11 millimeters per year – equivalent to a meter in 100 years. In the current situation with global warming, Aslak Grinsted believes, that the sea level will rise with the same speed – that is to say a meter in the span of the next 100 years.

Earthquake hits Papua New Guinea

A strong earthquake measuring 6.4 on the Richter scale rocked the eastern region of Papua New Guinea, 316km north of Port
Moresby and 3,463km southeast of Kunak, Sabah at 7.15am today.

The earthquake did not pose any tsunami threat, the Malaysian Meteorological Department said in a statement.

Northwest Lava Flows Could Have Altered Earth’s Climate, Wiped out Species, New Evidence Suggests

(Apr. 7, 2010) — New research suggests the volcanic birth of the Northwest's Columbia Plateau happened much more quickly than previously thought and with an intensity that may have changed the earth's climate and caused some plants and animals to go extinct.



"What you're looking at are lava flows that repeat fairly quickly," said Steve Reidel, research professor of geology at Washington State University Tri-Cities. "Not decades or centuries, but months or years."

Reidel is a co-author of a paper in the recent issue of the journal Lithos refining the time frame of the Grande Ronde lava flows, which produced enough molten basalt to sink the earth's crust and created the vast Columbia River Plateau of Washington, Oregon and Idaho.

Just one of the 100 or so lava flows would have blanketed much of Washington State in 10,000 cubic kilometers of lava -- 10,000 times the volume of ash produced by the 1980 eruption of Mount St. Helens.

The flows moved at walking speed, enough time for the horses and other animals of the region to get out of their path. But a single flow could reach as far as Portland, be more than 2,000 degrees Fahrebheit and take half a century to cool. In the process, it would have generated monsoons across the Northwest and emitted enough heat and sulfur to alter the earth's climate, said Reidel.

Substantial evidence has implicated other lava flows in the extinction of species. Siberian flows coincided with the epic Permian-Triassic "mass dying" that wiped out 96 percent of the earth's marine species 250 million years ago. A mass extinction at the end of the Triassic Period 200 million years ago coincided with lava coming out of the Central Atlantic Magmatic Province between what is now northeastern South America and eastern North America. Gases from flows on India's Deccan plateau started a mass extinction some 65 million years ago, with the dinosaur-killing coup de grâce coming from a meteoroid that hit Mexico's Yucatán Peninsula.

To date the Grande Ronde flows, lead author Tiffany Barry of Britain's Open University obtained basalt samples from Hanford, Wash., and outcrops between Vantage, Wash., and Lewiston, Idaho. With some of the most precise equipment in the world, she compared argon isotopes in the oldest, deepest levels and younger, shallower levels and used the element's decay rate to determine the rocks' relative ages.

Barry, Reidel, WSU Professor Emeritus Peter Hooper and other colleagues estimated the Grande Ronde flows took place between 15.6 and 16 million years ago, give or take 150,000 to 200,000 years. The youngest and oldest rock samples were only 420,000 years apart at the most. With a margin of error of 180,000 years, the rock may have been created over an even faster time frame of 240,000 years.

With less accurate equipment, Reidel and others previously estimated the flows occurred over a period of 1.5 to 2 million years. And because the Grande Ronde had so many flows, with some much larger than others, they likely had a far greater impact on the climate of their era than previously thought.

Some flows, wrote the researchers, "may have, at times, been simultaneous and, if confirmed, would have significant implications for potential environmental effects."

"It's an interesting piece of work and definitely a contribution," said John Wolff, a WSU professor in the School of Earth and Environmental Sciences, who was not involved in the paper. Both Wolff and the paper's authors note that the argon dating conflicts with dates established by looking at how changes in the earth's magnetic field affected the rock.

If the argon dating holds up, Wolff said, it will coincide with changes in the life forms and chemistry in the Atlantic Ocean. Just last summer, British researchers writing in the journal "Geology" described evidence of such changes off the west coast of Africa and singled out the Grande Ronde basalt flows as a possible cause.

Fighting for the beaches

Fighting for the beaches

Reclaiming land in Ghana

Written by Lynn

An ambitious sea defence scheme in Ghana could have been successful but the job is not finished and thousands of homes still flood annually.

In Keta, South Eastern Ghana, land was being eroded at up to 14metres a year. Since 1900, 100s of metres of land were lost including houses, churches and even the chief’s palace. The town on a narrow sand bar between the Atlantic and Keta Lagoon, which floods during the rainy season, was threatened from two sides.

In 1999 Ghana’s government secured a loan from the US Exim bank and started an US$84million scheme - a combination of groynes, a revetment and raising the level of the land near the lagoon. A sluice gate was built so flood water from the lagoon could run into the sea.
The four year project did not go as planned. The government was supposed to build 800 houses for people displaced by land reclamation work but only 230 families received new homes. A further 70 houses, in various states of completion, lie empty apparently because the contractors have not been paid. The remaining 500 homes have not materialised so people have moved away, are staying with family or living in temporary houses.

In the village of Vodza only a third of the land has been raised and thousands of residents continue to live in houses below the level of the lagoon, experiencing annual flooding so severe they visit neighbours by canoe.

Resident engineer, Rex Edeckor, is frustrated the work has not been completed. He said: “The government would love to build these places but there’s no money in the coffers.” He explained, despite flooding, the sluice gate has never been operated because of fears people will be swept out to sea and that fish will escape.

The sea defences are protecting the town from erosion but the government has not awarded a contract for their monitoring, so cannot benefit from the contractor’s 10-year guarantee. Within 15 years more sand will need to be pumped on to the beaches but Edeckor suspects the government has no money for this either.

Despite the millions spent, it seems this scheme can only be a temporary measure and if, or when, the sea level rises the work will have been largely in vain.

Edeckor predicted: “If sea level changes by one metre perhaps a third of Keta district will be flooded.”

To see more photos from Ghana click here --> http://www.atlanticrising.org/gallery/photo-view.asp?id=30

Tropics: Global Warming Likely to Significantly Affect Rainfall Patterns

Climate models project that the global average temperature will rise about 1°C by the middle of the century, if we continue with business as usual and emit greenhouse gases as we have been. The global average, though, does not tell us anything about what will happen to regional climates, for example rainfall in the western United States or in paradisical islands like Hawai'i.

Analyzing global model warming projections in models used by the Intergovernmental Panel on Climate Change, a team of scientists headed by meteorologist Shang-Ping Xie at the University of Hawaii at Mānoa's International Pacific Research Center, finds that ocean temperature patterns in the tropics and subtropics will change in ways that will lead to significant changes in rainfall patterns. The study will be published in the Journal of Climate this month, breaking ground on such regional climate forecasts.

Scientists have mostly assumed that the surfaces of Earth's oceans will warm rather evenly in the tropics. This assumption has led to "wetter-gets-wetter" and "drier-gets-drier" regional rainfall projections. Xie's team has gathered evidence that, although ocean surface temperatures can be expected to increase mostly everywhere by the middle of the century, the increase may differ by up to 1.5°C depending upon the region.

"Compared to the mean projected rise of 1°C, such differences are fairly large and can have a pronounced impact on tropical and subtropical climate by altering atmospheric heating patterns and therefore rainfall," explains Xie. "Our results broadly indicate that regions of peak sea surface temperature will get wetter, and those relatively cool will get drier."

Two patterns stand out. First, the maximum temperature rise in the Pacific is along a broad band at the equator. Already today the equatorial Pacific sets the rhythm of a global climate oscillation as shown by the world-wide impact of El Niño. This broad band of peak temperature on the equator changes the atmospheric heating in the models. By anchoring a rainband similar to that during an El Nino, it influences climate around the world through atmospheric teleconnections.

A second ocean warming pattern with major impact on rainfall noted by Xie and his colleagues occurs in the Indian Ocean and would affect the lives of billions of people. Overlayed on Indian Ocean warming for part of the year is what scientists call the Indian Ocean Dipole that occasionally occurs today once every decade or so. Thus, the models show that warming in the western Indian Ocean is amplified, reaching 1.5°C, while the eastern Indian Ocean it is dampened to around 0.5°C.

"Should this pattern come about," Xie predicts, "it can be expected to dramatically shift rainfall over eastern Africa, India, and Southeast Asia. Droughts could then beset Indonesia and Australia, whereas regions of India and regions of Africa bordering the Arabian Sea could get more rain than today."

Patterns of sea surface temperature warming and precipitation change in 2050 as compared with 2000. Annual mean precipitation change is shown in green/gray shade and white contours in mm/month. Precipitation tends to increase over regions with ocean warming above the tropical mean (contours of warm colors in oC), and to decrease where ocean warming is below the tropical mean (contours of cool colors).