Groundwater: The Solution to Climate Change?

As seen in previous blogs, freshwater resources and people will be highly affected by climate change.  As temperatures increase, there will be an increase in evapotranspiration, leading to a high loss of surface water resources, especially in dry areas.  People in semi-arid and arid countries in Sub-Saharan Africa are highly susceptible to changing patterns of freshwater availability.  However, groundwater may be the solution to all climate change problems, as it is highly available in aquifers.  This blog aims to assess groundwater as a barrier against climate change impacts, such as droughts.

Groundwater in Sub-Saharan Africa is estimated to occupy a volume of approximately 0.66 million  km³ of freshwater.  North Africa contains a large amount of Sub-Saharan’s groundwater storage, as Libya, Egypt, Sudan, Algeria and Chad contain the largest aquifers of the region (MacDonald et al 2012).  Furthermore, the Saharan region consists of large areas where groundwater recharge occurred almost 5000 years ago, even though no recharge occurs at present (MacDonald et al 2012). Hence, although Sub-Saharan Africa is relatively dry, there are large underground resources (Figure 1).   Thus, as precipitation events will occur less frequently and intensification of extreme events such as droughts will occur, there will be an increase of groundwater reliance.  These resources could be exploited for the provision of the domestic and agricultural water needs of people.

Figure 1: Groundwater storage for Sub-Saharan Africa
Source: MacDonald et al 2012

Groundwater could be a great solution, especially since the Millennium Development Goals (MDG), which consisted of the provision of clean and safe water for people to alleviate diseases.  This would also eliminate poverty as there would be enough water available for food production.   According to the data of 2012, 300 million people in Africa had no access to safe drinking water and a high proportion of the population was considered poor (MacDonald et al 2012). Hence, highlighting the importance of groundwater as a resource of exploitation. 

Problems

Nonetheless, if groundwater is exploited without adequate sustainability measures taken, the source will slowly diminish to an extent where people will be unable to use it.  As groundwater recharge will not occur as frequently and there will be an increase in demand of groundwater leading to diminishing groundwater resources (Carter and Parker 2009).  As it is expected that population will increase by more than half a billion, by 2050 this suggests that more people will need access to water resources (Taylor et al 2009).  Hence, with an increase in demand for food production and sanitary health, groundwater demand will increase substantially, especially in urbanised areas (Taylor et al 2009).  This may lead to overexploitation of groundwater resources, questioning for how long groundwater will be available if no substantial groundwater recharge occurs.  However, this may be highly variable, as there is not a lot of observed data sets of groundwater resources.  Therefore, there is high uncertainty of how groundwater recharge may be impacted by climate change impacts (Taylor et al 2009).

Another, issue may be that some of the groundwater is very deep and thus it is hard to pump out and it is away from remote areas, hence leading to high costs (Figure 2) (MacDonald et al 2012).  There may be a barrier in the ability of pumping groundwater from deep aquifers, as a high proportion of the population lives in deprived conditions and do not have the economic ability to invest in mechanical pumps of high power.  Moreover, many governments may not be able to provide large power pumps across the whole country to distribute the water (MacDonald et al 2012).  Thus unfortunately some areas will be unable to exploit groundwater resources to the desired degree.  Controversially, Taylor et al 2009 argue that groundwater infrastructure is relatively cheap compared to surface water infrastructure and maintenance of groundwater resources are cheaper, hence questioning to what degree this will limit the ability of people to abstract groundwater from deep aquifers.

Figure 2: Aquifer productivity for Africa. The inset shows an approximate depth to groundwater (Bonsor and MacDonald 2011)
Source: MacDonald et al 2012

Additionally, a problem may arise, if there is an increase in technological advancement and there are relatively no regulations.  People, may pump too much water and overexploit groundwater resources as they become wealthier (Carter and Parker 2009).  If groundwater recharge is lower than groundwater abstraction, this will lead to groundwater level declining and decreasing groundwater availability.   Carter and Parker argue that groundwater recharge best occurs in medium intensity rainfall.  Therefore, intensification in precipitation events may not provide the aspired groundwater recharge, leading to diminishing groundwater availability.

Lastly, many aquifers may be transbourdary, meaning they are beneath more than one country.  Hence, this creates hydropolitical issues (Taylor et al 2009).  As there is an increase in groundwater demand, due to increased climatic changes, there may be an issue of who uses the water and who gets a substantial degree of the groundwater source.  For instance increased groundwater abstraction in one nation may not allow rivers to be regenerated due to baseflow hence affecting a transboundary river. This may lead to many disagreements between nations and even wars.

Conclusion

With increasing climate change impacts this increases groundwater reliance.  Groundwater use combined with a technological advancement, is highly essential for the prosperity of the people.  However, if groundwater is overexploited it is questionable to what degree groundwater will be available and for how long.   Although groundwater may be a solution to climate change for a certain period of time, this does not mean groundwater will always be available to people.  Hence emphasising the importance of trying to monitor groundwater abstraction through government regulations to mitigate climate change impacts.

Adaption of farmers to Climate Change Impacts

Last week’s blog assessed agricultural impacts inflicted by climate change.  This week’s blog aims to analyse the ability of farmers to adapt to climate change impacts.  This will be evaluated, by looking at Ethiopia as a case study.

Local farmers observed an increase in temperatures and a decrease in precipitation over time (Deressa et al 2009).  Some farmers were able to assess changes in rainfall seasons, suggesting that rain in many cases may have occurred later than expected.  Therefore highlighting the observation of climate changes occurring in Ethiopia and the influence on farming (Deressa et al 2009). However, Bryan et al (2009) suggests that in most cases, these observations were variable depending on the age of farmers, farm and non-farm income and the degree of services.  Hence, questioning farmer’s degree of understanding on climatic change in the long run.

Wealth as a factor in climate change adaptation

In Ethiopia, the main source of wealth occurs from agriculture.  Deressa et al (2009) suggests that agriculture in Ethiopia contributes 85% of the foreign exchange earnings, employs 80% of the population and increases GDP by 35%.  Hence, agriculture provides economic security for many people.  However, this security is threatened due to environmental impacts forcing farmers to adapt to different agricultural processes.  Poor farmers tend to have less machinery and a smaller amount of land, hence are more willing to adapt (Bryan et al 2009).  Hence, due to not having a lot to loose in terms of economic benefits, poor farmers are willing to adapt their farming strategies to become more tolerant to climate change impacts.  Unfortunately they are unable to do so, as long-term measures against climate change impacts are costly (Deressa et al 2009).  Controversially, middle-income farmers are reluctant to agricultural adaptation, as a loss of agricultural yield may affect their food security and lower their standard of living (Bryan et al 2009).  Furthermore, wealthier farmers are more able to adapt.  They have more money, more machinery and their own radio (for telecommunication). Therefore, allowing them to adapt to a higher degree compared to other social groups.  Additionally, wealthier farmers with larger areas of land adapt more easily as a small decline in yields will not affect their income substantially (Bryan et al 2009).  Moreover, they are able to obtain credits from the bank and adapt better to climate change, as there is more cash flow to invest in machinery and increasing agricultural efficiency (Deressa et al 2009). 

Conversely, Conway and Schipper (2011) argue that there is no apparent correlation between changes in GDP and rainfall (Figure 1). This relationship is only apparent after the year 2000, as there is an intensification of climate change impacts and rainfall patterns change substantially. Hence, the slower the degree of change of climate, the less impact this will have on GDP (Conway and Schipper 2011).  This highlights that wealthy farmers have the opportunity to adapt but are not willing to adapt to new agricultural practises except if there are significant losses in agricultural yield. Their main incentive will be making a profit unless they are substantially affected by climatic events.

Figure 1: The relationship between rainfall and GDP in Ethiopia
Note: There is a relatively week correlation also highlighted by the correlation number of  0.1, suggesting no statistical significance
Source: Conway and Schipper 2011

Agricultural adaption due to extreme events

Furthermore, the most apparent relationship seen in Figure 1 occurs with extreme climatic events such as droughts.  Therefore, changes in the hydrological cycle caused by climate change will be vital when regarding changes in the economy of Ethiopia (and also many other countries).  Deressa et al (2009) draw the conclusion that farmers who had experience of extreme droughts or floods, are willing to adapt compared to farmers with less experience.  This may be highly correlated with experiencing losses in agricultural yield.  Bryan et al (2009) suggests that 14% of the people experiencing intense events are likely to change their farming practises.  This is achieved by: selling livestock, migrating, borrowing more money and receiving food aid.  However, Conway and Schipper (2011) suggest these measures are short-term and will not help in resolving long-term climate change impacts.  Hence, questioning to what degree Ethiopians are able to adapt due to climatic changes and economic constraints.

Climate change adaptation according to knowledge

Lastly, many farmers are willing to adapt their agricultural practises when having more knowledge about climate change.  The higher the understanding and awareness of environmental impacts on agriculture and water supplies, the higher the willingness of adaptation (Bryan et al 2009).  In many cases, wealthier and middle class farmers, find that knowledge is the best incentive and feel it is a key factor to being persuaded to change their agricultural skills and techniques (Figure 2). 

 

Figure 2: Various Factors influencing farmer's adaption
Note: Lack of Knowledge being one of the largest incentives for wealthy and middle class farmers to adapt against climate  change as they already have land
Source: Bryan et al 2009

Conclusions

Therefore, it is evident that farmers are willing to adapt to climate change for various reasons, extreme weather and knowledge being the most important.  However, policy makers must acknowledge the type of adaption required.  Policy makers need to ensure the long-term climate adaption for all farmers, as short-term adaptation creates false security (Conway and Schipper 2011). When adapting to short-term climatic changes, farmers will think that the measures they are taking are enough to withstand extreme events, even though this is not the case (Bryan et al 2009).  Although poorer farmers are willing to adapt, they are less able to take long-term adaptions, due to high costs, underlining a major barrier. Hence, guidance and some form of subsidy may be essential to achieve this goal for poor farmers.