The UN 2020 Water and Climate Change report summary - Chapter 9: Water - Climate - Energy - Food - Environment Nexus

 

The ninth chapter of the UN 2020 Water and Climate Change report focuses on the links between energy, food and agriculture, the environment, and the effects of climate change on water. The report stresses that adaptation and mitigation measures in one sector can, and are likely to influence water demand, thus affecting water availability for other sectors. Because this link between sectors, groups must assess and respond to the effects of climate change, and such an action has to be done as a collective. By working together, groups can combine their disciplinary knowledge to produce changes across sectors.

The energy perspective

The water sector requires energy and energy production requires water. The water sector’s electricity use is expected to double by 2040, but this can be avoided if water demand decreases (e.g. promoting lifestyle changes) and water management efficiency increases(e.g. making water infrastructure climate-resilient). The energy sector’s water use comes largely from growing biofuels, mining fossil fuels, and the cooling process in thermal power generation. By shifting to alternative energy sources that require relatively little water such as wind and solar photovoltaic, the energy sector can reduce its water consumption.

The food and agriculture perspective

69% of global water withdrawals come from the agriculture sector, highlighting the need for improved water efficiency in the sector. Improved efficiency will not only lead to increased water availability, but also reduce energy needed for getting water. By reducing the agriculture sector’s water and energy demands, they can lower greenhouse gas emissions and mitigate climate change.

Irrigation is a commonly understood method to increase water efficiency in agriculture, but it does not actually lead to water savings at larger scales. This is because farms that produce an already large amount of crops will take these water savings and produce even more crops with the same volume of water as before. The lack of actual water savings highlights the importance of conservation agriculture, which allows soils to retain more water and reduce water and energy demand.

Additionally, the agriculture sector and consumers produce a significant amount of food waste that contributes to global greenhouse gas emissions. By reducing food waste, we can also mitigate climate change.

The land use and ecosystem perspective

Healthy ecosystems can capture carbon far better than human efforts to do the same, but degraded ecosystems can in their turn be a source of carbon emissions. These ecosystems must be maintained and rehabilitated with improved water management. Efforts to improve land use, such as reforestation, will also impact ecosystems, therefore these potential impacts should be accounted for. The report stresses that any land use or ecosystem change in response to climate change should also take into account local environmental and socioeconomic conditions. 

The water supply, sanitation and wastewater treatment perspective 

Improved approaches to this sector can mitigate climate change, especially through treating and reusing wastewater. By reusing water in a circular water management system, the water sector can reduce the amount of energy it needs. Preventing the dispersal of wastewater is also important because wastewater is a source of greenhouse gases. One of the most effective ways to treat wastewater is by constructing wetlands, especially in places with operational and maintenance constraints.

Co-benefits

When water-related projects are carried out, there are broader socio-economic co-benefits, such as increased employment and income opportunities. Dar Si Hmad’s fog harvesting project, for example, has given women and girls in the communities we serve the time and opportunity to earn revenue  and go to school. The report states that water-related projects are more likely to get funding if their proposals state specific and realistic co-benefits across sectors.

Written by: Gari DeRamos, DSH's former intern