Defining a sustainable pumping rate for the Makutapora wellfield is complicated by the variable and episodic nature of groundwater replenishment in this dryland environment. For example, groundwater recharge during the 1997/1998 El Niño event, the strongest El Niño event of the 20th century, accounted for nearly 20% of all of the recharge received from 1955-2010 , highlighting the vital role interannual groundwater storage plays in enabling adaptation to climate variability and change in drylands. The disproportionate contribution of intense seasonal rainfalls to the replenishment of the Makutapora wellfield, consistent with observations from across sub-Saharan Africa , suggests that groundwater in drylands are currently naturally resilient to climate change. However, it remains unclear whether climate change will strengthen or weaken the influence of ENSO and IOD on rainfall  and thereby affect the predictability of groundwater recharge.
IPCC
Climate Change 2022: Impacts, Adaptation and Vulnerability
IPCC Report