|
| A heat dome has brought sweltering temperatures to the North America, beginning in Mexico and moving up over the western US. In Mexico, the hot dry weather has exacerbated water shortages as reservoirs threaten to dry up. One solution, as I found out this week, is to invest in greening its cities, using trees to help restore much-needed groundwater supplies. Doing so could help the city from a downward trajectory in more ways than one. Also in the wake of World Oceans Day we visit South Africa's famed but threatened sardine run and give humpback whales a health check. | |
|
|
|
|
CLIMATE CONVERSATION | Can trees keep Mexico's taps on? | | Mexico is no stranger to heatwaves and drought. Credit: Alamy | Mexico City, the most populous metropolitan area in North America, is parched.
In the midst of a severe drought, it's not uncommon for many of its 22 million residents to open the tap and find… nothing comes out.
"In the past few weeks, we have had water cut-offs," Alejandra Lopez Rodriguez of The Nature Conservancy told me in a recent interview. "Sometimes there is water in the morning and in the evening. But during the day, the water is shut off, I guess to preserve the water volume and start rationing it."
For residents, that can mean collecting used shower water in buckets to flush the toilet. Others wait for private trucks to refill centralised water tanks in their apartment building. The least fortunate have no running water at all. |
|
|
|
| As mayor of Mexico City, Claudia Sheinbaum advocated for solar energy and public transport reform. Credit: Getty Images | Lopez Rodriguez, The Nature Conservancy's Mexico water and climate solutions director, points out this isn't a new problem. Mexico City has faced water shortages before – but this year it's "critical".
The Cutzamala System of reservoirs, canals and tunnels supplying about a quarter of the city's water is rapidly drying. In late May, the system was at a historic low: just 28% of its capacity, according to Mexico's Water Department, Conagua. |
|
|
|
Dry and sinking | The shortage is due to a mix of population growth, leaky infrastructure, heat waves and a prolonged drought. Scientists are studying a direct link to climate change, but the recent trend is clear: Mexico is facing a chronic water shortage. Droughts classified as "extreme" and "exceptional" now affect several states in Mexico.
As well as water from nearby reservoirs, groundwater extraction is also used to keep Mexico City's taps running. So much water is removed, now and historically, that the city is sinking – in some areas cases up to 20 inches (50cm) per year.
One solution is to build water security through nature. The Mexico City Water Fund, which includes The Nature Conservancy and other development groups, is helping protect the region's green areas, which are crucial to capture rainfall to replenish groundwater, and also reduce risk of flooding.
"The forests which surround the city are the areas where the water gets recharged to the aquifer. So protecting those forests and protecting that aquifer is extremely important for our water provision and our water security," says Lopez Rodriguez. | A new chapter | The drought will be one of the first challenges awaiting Mexico's newly elected president, Claudia Sheinbaum – the nation's first female president, who is also a climate scientist and former mayor of Mexico City.
"There are a lot of expectations," says Lopez Rodriguez. "She has campaigned on making sure that there will be water for all people, rich and poor, and of all genders. So, we are hoping that she will deliver on that promise."
Mexico City isn't the first city to run low on water – and it likely won't be the last. In 2018, Cape Town survived it's own severe water crisis. Bogota is currently rationing its water amid a historic drought.
"We need to look at what are our sources of water in nature and protect those sources that we depend on for our life and productive activities," says Lopez Rodriguez.
Read India Bourke's story on how Claudia Sheinbaum's climate science experience could inform her presidency, and Melissa Hogenboom's feature on Mexico City's long-term battle with drought. | |
|
|
|
|
NUMBER OF THE WEEK | 33.5 metres | The length of a typical blue whale (that's 110ft). Underwater photographer Pier Nirandara shares 13 stunning images that he took to inspire people to care about protecting the oceans from climate change and degradation.
| |
|
|
|
TAKE A MOMENT | How much do clouds affect climate? | The Climate Question reports on how a satellite mission aims to find out. | |
|
| |
|
|
CLIMATE QUIZ | D-Day shipwrecks in the English Channel are having an unexpectedly vibrant afterlife – what has made the wrecks their home? | A. Fist-sized, mushroom-like sea anemones | B. Barnacles, starfish, scallops and sea urchins | C. Conger eels, tube worms and soft corals | Scroll to the bottom of this newsletter for the answer.
|
|
|
|
| THE BIG PICTURE | The fate of South Africa's sardine run | | South Africa's sardine run is one of the world's great migrations. Credit: Alamy | One of nature's great mass migrations happens each year off South Africa's coast, in the form of a torpedo-like mega-shoal of sardines following cool, nutrient-rich ocean currents. The "sardine run" is mass migration that doesn't go so well for the fish, leading them into danger and the jaws of predators. Those lucky predators include the endangered African penguin, Cape cormorant, Cape gannet and school shark. Climate change, however, contributing to the decline of the sardine run. Katherine Latham explores what this means for the diverse food webs that rely on the fish. | |
|
|
|
|
BEFORE YOU GO | - Air pollution has been linked to girls getting their first period at a younger age, David Cox reports.
| | | |
|
|
|
AND FINALLY... | Braving 12m (39ft) waves in the Southern Ocean, a custom-made crossbow in hand, researchers are looking for humpback whales to take stock of their health and how they are faring in warmer seas. The crossbow is adapted to take skin and blubber samples from the whales, says scientist Natalia Botero-Acosta, and it's not a weapon. Watch as BBC News' Victoria Gill and Kate Stephens travel to the Antarctic Peninsula for a humpback health check. |
|
|
|
No comments:
Post a Comment