Climate Change & the Nexus (DP IB Geography)
Revision Note
Climate Change & the Water, Energy & Food Nexus
What impact will climate change have on water supplies?
There are a number of ways that water supplies are affected by climate change, these include:
Unpredictable rainfall
Floods
Droughts
Rising sea levels
Melting ice sheets/glaciers
Climate change is impacting on the amount of available freshwater
The UN predicts that by 2050, up to 5 billion people worldwide will face freshwater shortages
The melting of glaciers and ice sheets has led to an estimated 3% reduction in freshwater storage since 1971
Salinisation of groundwater is increasing annually at a rate of 10% due to salt intrusion caused by sea level rise
This decreases the amount of freshwater available in coastal areas
Higher water temperatures, droughts and floods decrease water quality
More frequent droughts may lead to increased soil degradation and desertification in areas such as the Sahel
This will impact on food production due to a lack of water for irrigation
Fewer trees and vegetation will mean less biomass for energy production, particularly in areas where people rely on fuelwood for heat and cooking
High-income countries such as the USA and Australia also face water shortages but this is less likely to impact food and energy security because they can afford to import
What impact will climate change have on food supply?
Crops and livestock
Increased temperatures and changes in rainfall patterns affect crop yields
Decreasing freshwater supplies have an impact on:
The availability of irrigation
Water for livestock
Increased floods, which destroy crops
Crop yields are impacted through:
Declining water quality
Soil degradation and desertification
Climate change is also affecting the areas affected by pests and diseases, expanding their geographic range
Tar spot is a fungal disease affecting maize
It was native to Latin America
It can lead to a 50% reduction in yields
In 2015, it was detected for the first time in the US
The spread of invasive, non-native species due to higher temperatures can impact food systems
Fish stocks
Increased sea and river temperatures may affect:
Fish breeding patterns
Fish populations
Increased algae growth, which contaminates seafood
Decreases in water quality impacts fish and seafood
What impact will climate change have on energy supply?
Changing weather patterns may impact renewable energy supplies
Reduced cloud cover may lead to increased solar power
Changing wind patterns may impact the use of wind energy
Reduced precipitation may lead to challenges in growing biofuels
Increased water scarcity will reduce the amount of water available for irrigation
As the amount of water stored in glaciers reduces, the spring snowmelt will result in lower discharge
This will affect the amount of energy generated by hydropower
Tajikistan is reliant on hydropower and is already experiencing changes in river flow
Sea ice melt in the Arctic may improve access to gas and oil reserves
Increasing the availability of fossil fuels
Reducing the cost of extraction
Last updated:
You've read 0 of your 10 free revision notes
Unlock more, it's free!
Did this page help you?