Water management has a bigger role to play in helping countries mitigate and adapt to climate change, according to a new report from the United Nations.
The Water and Climate Change report, which was released this month to mark World Water Day, also warned that, with climate change exacerbating water scarcity around the world, even countries with comparatively good water infrastructure such as Australia need to prepare for increasing water stress over the coming decades.
It said Australia’s natural aridity and water withdrawal means it will face rising water stress and, like other nations, must improve its efficiency of water use in agriculture and industry, as well as develop better wastewater treatment.
“As the planet warms, water has become one of the main ways we experience climate change,” said Audrey Azoulay, Director-General of UNESCO, in a foreword to the report.
“The report shows that water does not need to be a problem – it can be part of the solution. Water can support efforts to both mitigate and adapt to climate change.
“Wetland protection, conservation agriculture and other nature-based solutions can help to sequester carbon in biomass and soils. Improved wastewater treatment can help reduce greenhouse gas emissions and produce biogas as a source of renewable energy.”
The report called for measures to improve how we use and reuse water, and outlined actions required for adaptation and mitigation as “complementary strategies” for dealing with the effects of climate change, particularly in areas where we are already observing the effects of decreased rainfall, such as southwestern Australia.
When it comes to agriculture, “climate change will fundamentally alter global food production patterns as a function of water availability” which in turn “presents a major challenge for climate adaptation”.
For Australia, it is estimated that between 2020 and 2060, some 28% of land currently dedicated to growing wheat will receive less rain under current trends.
We may also see changes in our ability to produce renewable energy needed to lower greenhouse gas emissions, with the report estimating that by the 2050s, climate change could produce a reduction in hydropower capabilities of up to 3.6%, as well as a 7% to 12% in thermoelectric power.
With around two-thirds of the world’s anthropogenic greenhouse gas emissions coming from energy production and use, renewables are more critical than ever to counteracting climate change and relieving water scarcity.
It has been estimated that in 2030, these renewable energy sources could be responsible for about a 50% reduction in water withdrawals in the United Kingdom, and over 25% in the United States and Australia.
There is some good news, with the Springvale Mine in Lithgow, New South Wales given as an example of effective reuse of water in industrial water management.
The mine produces coal for use at the nearby Mount Piper Power Station, which provides about 15% of the state’s power. The mine water is treated and delivered via a 16 km pipeline to the power station for reuse as cooling water, which the report says “ensures environmental and operational compliance in relation to water outflows and, most importantly, enables continued operations of both the mine and the power station”.
In addition to the effects of water withdrawal capabilities, such as our ability to use it for agriculture, domestic supply and power generation, the report notes that “the combined impact of changes in precipitation and evaporation will also determine future trends in soil moisture and groundwater, with potential consequences for the frequency and severity of soil moisture drought spells”.
Read the report here.