$30 trln in additional investments required to achieve net zero in 8 hard-to-abate sectors
The Net Zero Industry Tracker 2024 estimates that $30 trillion in additional capital will be required across ...
River flow decreased in 402 basins worldwide over climate change, land use – reports
River flow has decreased in 402 basins worldwide – a fivefold increase since 2000 – over climate change and land use. A much smaller number is gaining in river flow.
This came in the findings of three reports tracking progress on freshwater, published by UN-Water and the UN Environment Program (UNEP).
A reported 90 countries, most in Africa, Central- and Southeast Asia, are experiencing the degradation of one or more freshwater ecosystems. Other regions, such as Oceania, mark improvements. Pollution, dams, land conversion, over-abstraction and climate change contribute to degradation of freshwater ecosystems.
Loss of mangroves due to human activities (e.g., aquaculture and agriculture) poses a risk to coastal communities, freshwater resources, biodiversity, and climate due to their water filtration and carbon sequestering properties. Significant decreases of mangroves were reported in Southeast Asia, though the overall net rate of deforestation has leveled off in the last decade.
Lakes and other surface water bodies are shrinking or being lost entirely in 364 basins worldwide. A continued high level of particles and nutrients in many large lakes can lead to algal blooms and low-oxygen waters, primarily caused by land clearance and urbanization, and certain weather events.
Nevertheless, the construction of reservoirs contributes to a global net-gain in permanent water, mainly in regions like North America, Europe, and Asia.
The poorest half of the world contributes under 3 percent of global water quality data points, including only 4,500 lake quality measurements out of almost 250,000. This reveals an urgent need to improve monitoring capacity.
Lack of data on this scale means that by 2030 over half of humanity will live in countries that have inadequate water quality data to inform management decisions related to address drought, floods, impacts from wastewater effluents and agricultural runoff.
Where good data are available, it shows that freshwater quality has been degrading since 2017. Where data are lacking, the signs are not promising.
Report authors recommend the expansion and development of routine government-funded monitoring program, as well as incorporating citizen science into such national programs, and exploring the potential of satellite-based Earth observation and modeled data products to help fill the data gap.
“Our blue planet is being rapidly deprived of healthy freshwater bodies and resources, with dire prospects for food security, climate change and biodiversity,” said Dianna Kopansky, Head of the Freshwater and Wetlands Unit, Ecosystems Division at UNEP. “At this critical point, global political commitments for sustainable water management have never been higher, including through the passing of a water resolution at the last UN Environment Assembly in February, but they are not being matched by required finance or action. Protection and restoration policies, tailored for different regions, are halting further loss and show that reversing degradation is within reach. We absolutely need more of them.”
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