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At least five million people in central Vietnam are facing disaster as the country battles its worst floods in decades.

So far, flooding and landslides in October have killed over 100 people, and left dozens more missing. The Red Cross says in a statement, “Everywhere we look, homes, roads and infrastructure have been submerged.” 

The country has been hit severely by heavy rainfall in recent weeks, which the Red Cross attributes to the “combination of numerous weather systems – the Inter Tropical Convergence Zone combining with cold air as well as tropical storms Linfa and Nangka.”

It continues, “Tropical Storm Linfa made landfall in Quang Nam and Quang Ngai provinces in Central Vietnam on October 11 and brought 150 to 300 millimetres of rain. Tropical Storm Nangka made landfall on October 14 in the northern provinces of Vietnam which brought along a further 150 millimetres of rain.”

At least 712 houses have been destroyed while at least 178 000 have flooded. Food crops have been destroyed and nearly 700 000 poultry and livestock have been killed or swept away. 

The floods come as Vietnam is already dealing with the economic fallout of the COVID-19 pandemic. Red Cross official Christopher Rassi says, “We are seeing a deadly double disaster unfold before our eyes as these floods compound the difficulties caused by COVID-19. These floods are the last straw and will push millions of people further towards the brink of poverty.”

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More rain is expected in the coming says, raising fears that floodwaters could rise further. 

While it is certainly difficult to pin extreme weather events such as these purely on the climate crisis, a recent UN report found that natural disasters have nearly doubled over the past 20 years, in line with increasing temperatures and rising greenhouse gas emissions.

Featured image by: Flickr

In early July, Venice tested its long-delayed flood barriers, in a public demonstration of the strength of the barriers months after floods swamped the city. 

The multi-billion-euro Mose (Experimental Electromechanical Module) scheme, which was still incomplete a decade after it was due to come into service, has been plagued by corruption and ever-inflating costs. The test saw all 78 giant yellow sluice gates rising above the water for the first time, but it is not expected to be fully functional until next year. Once fully operational, the Mose flood barriers system is designed to protect Venice from tides of up to three metres, which is well beyond the current record, but some experts are concerned that it will be overwhelmed by the rising seas that recent climate change models have predicted. 

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Additionally, the test was carried out in ideal conditions, far different from the 100kph winds and three metre waves that struck the city last November. Further, while all gates can go up, not all can currently go back down into their housings on the sea floor, due to sand in the works.

In November 2019, the worst floods in more than 50 years submerged 70% of the city at one point and rose to over 1.8 metres in some areas. Venice’s floods, called “acqua alta” (high water) are caused by rising sea levels and unusually high tides due to land subsidence that has caused the ground level of the city to sink. 

There are also concerns that Italy won’t be able to keep up with Mose’s astronomical costs, estimated at around €100m a year. Adding to the government’s borrowing to restart the economy following the COVID-19 pandemic that may push public debt to 160% of GDP, this may be an expense that is difficult to maintain.

To keep the sea level in the city from rising any more than it already is, keeping big ships out of the lagoon may help. However, Pietro Teatini, professor of hydrology at Padua university, believes that Venice should be lifted. He says that doing this by 20-30cm would help and to do this, seawater could be pumped into the already salty aquifers below the city. In 2008, it was estimated that a pilot scheme would cost €11.1m to launch and €1.4m a year to run; the full project around €80m and €10m a year. In comparison, the Mose scheme has devoured €6bn. 

Featured image by: Roberto Trombetta

Weeks of torrential downpours in China have caused the worst flooding of the Yangtze River in the eastern province of Jiangxi since 1998, with floods impacting 38 million people and killing at least 140, the country’s Ministry of Emergency Management says. 

On July 13, the Changjiang Water Resources Commission’s hydrology bureau said the flood has passed its peak in the Jiujiang region, leaving it with a water level of 22.81m, the highest since 1998, when massive floods killed more than 3 000 people. 

On July 12, Chinese authorities raised the country’s flood alert to the second highest level in a four-tier emergency response system. President Xi Jinping has called for ‘stronger and more effective measures to protect lives’.

The floods have ravaged 8.72 million acres of farmland and according to state news agency Xinhua, by July 12, the floods had caused USD$11.75 billion of economic losses throughout China.

While live monitoring shows that Yangtze has stabilised, other water bodies in the area, including the country’s largest freshwater lake, Poyang, continue to pose a threat and other provinces in the flood’s path are waiting their turn. On July 13, the lake reached a historic high of 22.6m, but its waters are now expected to slowly recede over the next few days.

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Water levels at the Three Gorges reservoir, which cut its discharge volumes for a fifth time on July 11 to ease downstream water levels, have now risen to 153.2 m, 6.7 m higher than the warning level.

While summer floods are not an unusual occurrence in China due to seasonal rains, this year’s downpours are particularly bad. Flooding has hit 27 out of the 31 provincial regions in mainland China, with the average precipitation in the Yangtze River basin reaching the highest level recorded since 1961

Chen Tao, the chief weather forecaster at the National Meteorological Center, was quoted as saying, “Compared with before, this year’s rainfall was more intense and repeatedly poured down on the same region, which brought significant pressure on flood control.”

443 rivers throughout the country have been flooded, with 33 of them rising to the highest levels ever recorded, the Ministry of Water Resources said. The majority of these rivers are in the basin of the Yangtze River, which flows from west to east through densely populated provinces of central China. The river is the most important waterway in the country, irrigating large areas of farmland and linking inland industrial metropolises with Shanghai.

Ye Jianchun, vice minister of water resources, told a briefing on Monday, “Going into the key flood-prevention period of late July to early August, the current trends remain grim on the Yangtze and the Lake Tai basins.” He added that the belts of heavy rain that have lashed central China would eventually head north.

China’s weather bureau said that although some regions in the southwest would see a temporary respite from the heavy rain, central and eastern China would continue to bear the brunt of the storms. On July 14, the China Meteorological Administration issued a blue alert for heavy rain until Saturday in provinces in the country including Sichuan, Hubei, Anhui, Jiangsu and Zhejiang. 

In the meantime, residents along the Yangtze River and in the Poyang Lake region continue to implement their own series of defence measures, securing riverbanks and fortifying dykes with sandbags to prevent entire villages being submerged. 

Featured image by: LanguageTeaching

New research shows that warming temperatures in the Indian Ocean could lead to the return of an ancient El Niño- style system not seen since the Ice Age that may increase storms, floods and droughts that occur around the Indian Ocean, impacting vulnerable regions already threatened by the climate crisis.

The study, published in Science Advances, shows that small surface temperature increases in the Indian Ocean could see its associated weather patterns start to match the El Niño patterns currently seen over the Pacific Ocean, as soon as 2050. This matches up with how winds and rainfall used to affect the region during the last ice age, at least 21 000 years ago. This threatens some of the people that are already at extreme risk from the climate crisis, across Africa, Asia and Australia. 

Pedro DiNezio, one of the lead authors of the study, says, “Our research shows that raising or lowering the average global temperature just a few degrees triggers the Indian Ocean to operate exactly the same as the other tropical oceans, with less uniform surface temperatures across the equator, more variable climate, and with its own El Niño.”

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The Indian Ocean Dipole and the Australia Fires

El Niño is a weather system characterised by unusually warm water in the Pacific Ocean off the coast of Peru and Ecuador. It is linked to droughts in Australia and heavy rains in South America and is exacerbated by the climate crisis.

The researchers analysed 36 different climate models, picking out the ones that matched current weather conditions most accurately. These models were then used to examine how further warming might change the meteorological conditions around the Indian Ocean.

Currently, the Indian Ocean sees little change in temperature year-on-year; the west-to-east winds tend to keep conditions stable. However, the models show that the climate crisis may reverse these winds, completely altering weather patterns in the region. The study shows that the rising temperatures of today are affecting the Indian Ocean in a similar way as the glaciers did tens of thousands of years ago.

This could lead to increased flooding in some areas to longer dry spells in others, affecting massive parts of the world already feeling the effects of the crisis, as seen recently with the bushfires in Australia. 

These studies are valuable in showing the future impacts of human activity on the planet, and allow countries to plan to a certain extent, however in many countries, there simply are not enough resources to plan for the climate crisis in a meaningful way. 

DiNezio says, “We are certain that the risks of these extreme events are becoming larger and larger as we pump more CO2 into the atmosphere, and certainly going to have an unequal impact on countries in the tropics.”

Featured image by: Jon Sullivan

A new UN report has warned that climate change could trigger a global food crisis. The report outlines possible solutions including sustainable land management and increasing food productivity.

How will climate change affect food production?

The United Nations climate report warns that the world might face a food crisis due to climate change and overexploitation of land and water resources. A steady increase in global temperatures will make things worse, as floods, drought, storms, and other types of extreme weather threaten to disrupt the global food supply. 

The Intergovernmental Panel on Climate Change (IPCC) report, prepared by more than 100 experts from 52 countries and released in Geneva last week, reveals that humans affect more than 70% of ice-free land and a quarter is already degraded. Rapid agricultural expansion has led to destruction of forests, wetlands, grasslands, and other ecosystems. Soil erosion from agricultural fields is 10 to 100 times higher than the soil formation rate. Such rapid land degradation has created spinoff effects.

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“When land is degraded, it becomes less productive, restricting what can be grown and reducing the soil’s ability to absorb carbon,” says the report. “This exacerbates climate change, while climate change in turn exacerbates land degradation.”

The report also reveals that an estimated 23% of all greenhouse gas emissions that significantly warm the planet are caused by agriculture, cattle rearing, and deforestation. 

A warming atmosphere intensifies the world’s droughts, heat waves, wildfires, and other weather patterns, and it is further speeding up the rate of soil loss, land degradation, and desertification. “Since the pre-industrial period, the land surface air temperature has risen nearly twice as much as the global average temperature,” the report says “climate change, including increases in frequency and intensity of extremes, has adversely impacted food security and terrestrial ecosystems as well as contributed to desertification and land degradation in many regions.”

Possible solutions 

Warning that the window to address threats of climate change, food security, and land degradation is closing rapidly, the report offers a variety of solutions to address the challenges. 

Tactics like improving food productivity and increasing the carbon content of soil can simultaneously mitigate climate change, help regions adapt to warming, stop desertification, reverse land degradation, and enhance food security.

“The options with medium to large benefits for all challenges are increased food productivity, improved cropland management, improved grazing land management, improved livestock management, agroforestry, improved forest management, increased soil organic carbon content, fire management, and reduced post-harvest losses,” the report says.

Enhancing food productivity means using less land for agriculture, which could help preserve forest land retaining a natural carbon intake system. Those forests move moisture through the biome and help regulate temperature, reducing the impacts of warming. Trees in the preserved forest anchor the soil, slowing erosion and preventing desertification. That stabilising effect in turn helps reduce volatility in crop yields, enhancing food security.

Sustainable land management is an effective solution. “Land management can prevent and reduce land degradation, maintain land productivity, and sometimes reverse the adverse impacts of climate change on land degradation. It can also contribute to mitigation and adaptation,” says the report. “Reducing and reversing land degradation, at scales from individual farms to entire watersheds, can provide cost-effective, immediate, and long-term benefits to communities and support several Sustainable Development Goals (SDGs) with co-benefits for adaptation and mitigation.” 

Reducing food waste is another important solution. The report estimates that over 30% of food is lost or wasted, which has environmental costs as food waste accounts for upward of 10% of global greenhouse gas emissions. If the world were to drastically limit food waste, farmers would need less land, less fuel, less water, and less fertiliser, all of which would translate to a smaller environmental footprint. “Technical options such as improved harvesting techniques, on-farm storage, infrastructure, transport, packaging, retail, and education can reduce food loss and waste across the supply chain,” the report states. “By 2050, reduced food loss and waste can free millions of square kilometers of land.”

With many rivers dwindling and the groundwater in India nearly exhausted, an acute water scarcity crisis is underway in the world’s second-most populous nation.

Causes of Water Scarcity in India

Taps have run dry in India as millions of people brace themselves for the dreaded blend of extreme heat and water shortages during the summer. A combination of climate change, inefficient water use, and inadequate infrastructure has thrown India into a full-blown water scarcity crisis, forcing the government to create a brand new ministry–‘Jal Shakti Ministry’–to tackle the issue.

Water Scarcity in India: Statistics

This year, more than 330 million people are affected due to water scarcity as half of the nation’s land area grapples with drought-like conditions. 12% of the population, majority of them living in metropolitan cities like Bengaluru, Chennai, Delhi, and Hyderabad, are already facing the ‘Day Zero’ scenario, wherein most of their water supplies came to a complete halt. As many as 21 major cities including the national capital–New Delhi–is poised to run out of groundwater next year, according to a report by government-run think tank NITI Aayog. 

By definition, India now is a water-stressed country, where annual per capita water availability is below 1500 cubic metres. Half a century ago, it was 5200 cubic metres.

An assessment by the government indicates that the nation is gradually inching towards a calamity with the annual per capita availability likely to drop below 1000 cubic metres.

Climate change has pushed India’s climate towards extremes disrupting the quantity and frequency of rainfall. The country witnessed below average monsoon for the last two consecutive years. The North-East monsoon which provides 10-20% of India’s rainfall was deficient by 44% in 2018 as per data from the India Meteorological Department (IMD). This compounded the rainfall deficit in the South-West monsoon that provides 80% of the country’s rainfall, which fell short by 10% last year. Lower rainfall has reduced water levels in reservoirs across the country. During the first half of this year, 91 major reservoirs recorded 32% drop in their water capacity.      

Chennai, a coastal city of 10 million, had 55% less rainfall this year. The city went without rain for 200 days with its four water reservoirs turning into puddles of cracked mud causing the worst water scarcity crisis in 70 years.

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Puzhal reservoir in Chennai, India, has been reduced to a dry lake bed in just one year.

Unusual temperatures caused by climate change have made rainfall erratic with significant changes in monsoon patterns making droughts and floods more common in many parts of India. In 2015, a massive flood, spurred by unusually massive rainfall, devastated Chennai killing more than 500 people and leaving the city ravaged. Last year, flash floods in the states of Kerala and Karnataka caused distress while cyclones wreaked havoc in Tamil Nadu and Odisha.

India is rated ‘high risk’ in the Climate Change Vulnerability Index with major Indian cities are projected to experience a higher number of consecutive drought days with less rainfall in the near future. Changes in temperature, precipitation, and humidity will significantly impact the quality and quantity of water across the country, where water resources are also under unprecedented pressure from population growth, rapid urbanisation, and inefficient water use.

The water scarcity crisis is not unique to India. Globally, over 880 million people–about one in every nine people in the world–do not have access to clean water within 6 km of their homes. The United States Agency for International Development (USAID) predicts that approximately one-third of the world population will face chronic water crisis by 2025.

Freshwater constitutes only 2.5% of the total water on our planet and much of it is trapped in icecaps and glaciers, making it inaccessible for us. In reality, a meagre 0.007% of the planet’s total water is available to feed its 7.7 billion people.

India Water Crisis: Solutions

To avoid the impending water crisis, India and other vulnerable countries need effective climate change adaptation strategies that reflect the importance of water management in reducing vulnerability and building climate resilience. It is also necessary to bring in technology to help harness water more efficiently and build long-term water conservation plans.

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Two-thirds of Earth’s 242 longest rivers are no longer free-flowing due to human activities, a study mapping over 12 million kms of watercourses reveals. 

Why are free-flowing rivers important?

Besides dams and reservoirs, activities like water extraction and sediment trapping disrupt rivers’ natural flow. Free-flowing rivers feed hundreds of millions of people, deliver sediments crucial to agriculture and mitigate the impact of floods and droughts. River fragmentation and alteration threaten vital ecosystems for people and wildlife.

This groundbreaking study by hydrologists from McGill University, published in Nature, is the first comprehensive global assessment of the connectivity of Earth’s largest rivers. Scientific wisdom postulates that free-flowing rivers must remain connected across four dimensions: longitudinally, so that fish and other species can move upstream while water, nutrients, and sediments can move downstream; laterally, so the river can move out onto its floodplain, delivering important nutrients to fish in other habitats and bringing nutrients back into the river itself; vertically, so the river can flow into and interact with groundwater and aquifers; and seasonally, so that the important ecological functions rivers provide over time are not impaired — for example, the flood pulses that signal fish to spawn.

Using satellite imagery and hydrological modelling, researchers mapped over 12 million kilometers of watercourses worldwide.  The team identified indicators at the global scale that measured any of the four ways of river connectivity. Measurements showed how the presence of dams affects longitudinal, lateral, and seasonal components of connectivity. Roads and urban areas built in flood plains also disrupted lateral connectivity.

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Figure 1 River connectivity of global rivers threatened by the five dominant pressures: DOF (degree of regulation), SED (sediment trapping), USE (consumptive water use) and URB (urban areas) (Source: Grill et al. 2019)

Data analysis revealed that river fragmentation, flow regulation, sedimentation, water consumption, and urbanisation were the five dominant constraints rivers face worldwide. Only rivers in remote regions like the Arctic and the Amazon rainforest were found to have remained untouched and could flow unimpeded along its entire course. In densely populated areas only a few very long rivers remain free-flowing, such as the Irrawaddy in Myanmar and the Salween in China.

There are over 2.8 million large and small dams constructed around the world; these are the leading cause of river fragmentation. Dams, intentionally designed to impede river flow, not only alter terrestrial and freshwater biodiversity by preventing species migration, but also accelerate the shrinking of downstream river deltas and expose low-lying regions to increased flood risk by preventing the exchange of sediments.

This study adds to growing evidence highlighting how human activities are fundamentally changing the natural landscape and the water cycle. With more than 3,700 dams in the works and the pace of hydropower development accelerating around the world, the ecological consequences of dams should push us to develop an energy system that minimises negative impacts on our ecosystem. The results of this study, freely available in an interactive map portal, should serve as a wake-up call to policymakers, engineers, and planners and encourage them to redesign the infrastructure development projects.

Life in and around a river evolves and is conditioned by free-flowing water. A dam disrupts life.

The best way forward is to adopt nature-based solutions (NbS), which are defined as ‘actions to protect, sustainably manage, and restore natural or modified ecosystems, that address societal challenges effectively and adaptively, simultaneously providing human well-being and biodiversity benefits’. Countries should embrace NbS like floodplain restoration, ecological engineering, and integrated water resources management to ensure river flow connectivity and protect the ecosystem.

Removing dams is another way to restore the rivers. A dam removal movement has already started in the US, where about 1,500 dams have been removed. Support for river restoration through dam demolition is also growing in Europe and Japan.  A project called Dam Removal Europe focuses on clearing rivers of the 30,000 old or obsolete dams that still exist across Europe. These projects should be embarked upon more widely to ensure the protection and longevity of Earth’s last free-flowing rivers.

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