One of my colleagues shared this article from Truthout with me because the title was about how Alaska has no sea ice within 150 miles of its coastline for the first time in recorded history of Alaskan sea ice. That’s another checkpoint in the decline of summer sea ice, for sure, but the article included many signs of global warming changing our climate and impacting animals and people. One of the litany of climate woes they cite was a drought in Zimbabwe. In July this year, the Zimbabwean government declared an emergency because taps were running dry in the capital of Harare and water levels were so low that hydroelectric power ceased, causing widespread blackouts.
The city of Harare reported producing 450 million liters of water per day for 4.5 million people — so 100 liters per day per person on average. (The above article, though, cites cynical estimates that the real number is 1/4 of that.) To put this in perspective, Americans average over 300 liters of water per day. In 2018, Cape Town, South Africa barely avoided “Day Zero” during their own drought. “Day Zero” was the day that municipal taps would be turned off and residents would receive a ration of 25 liters or water per day. They prevented that level by millions reducing use to about 50 liters per day for a prolonged period. Cape Town sounds worse, then, even without reaching Day Zero.
Figure 1: Screenshot of Google Maps showing Zimbabwe in Southern Africa.
Two interesting ripples in this story, though:
First, the socioeconomic and political situation in Zimbabwe is less stable than in South Africa. Long-time despotic leader Robert Mugabe died on September 6, 2019. News outlets in the USA as diverse as Fox News and Vox have maligned him as a brutal dictator who oppressed his country and brought economic ruin. Before his death, reports of protests in the streets by those opposed to the regime (an especially the economic turmoil) trickled through Western media outlets (examples at the Guardian and NPR). This turmoil clearly goes beyond one drought, and the acuteness with which the drought is impacting Zimbabweans may have more to do with social vulnerability than physical hazard.
Second, is this really about climate change? Every news outlet I’ve read seems to have no problem attributing the drought to climate change despite providing no evidence that this drought is unprecedented or part of a larger pattern. There is evidence that droughts have become more common in parts of the world, such as the Mediterranean (see this NY Times article), but not everywhere. The answer for Southern Africa is: maybe. According to a study in the journal Natural Hazards, droughts in Southern Africa became more severe over the the course of the 20th century, in part because of long term global warming. However, using a combination of evidence from observational studies, the latest report from the Intergovernmental Panel on Climate Change (IPCC) did not find significant increases in the annual maximum in the number of consecutive dry days in Southern Africa.
- Figure 2: Trends in the maximum number of consecutive dry days each year (CDD) 1951 -2010. The plus signs indicate significant trends.
Thank you Dr. Crawford, lots of complexity. Your posts underscores how tricky and political reporting/blaming climate change can potentially be.
At the risk of piling on, we must first look at population demographics and relate it to geography. Situated near the Tropic of Capricorn, much of southern Africa is at the dicey location where desertification runs its natural course, a result of the mega-scale atmospheric circulation cells at the sub-tropical high. Superimpose rather large increases in population over the last century on a climate that already teeters near desert conditions, it’s rather easy to see that what might be called climate change by the news media, and others, is mainly the result of too many people fighting for too few resources, in an area that cannot withstand the pressure. Desertification in sub-Saharan Africa, under the same atmospheric conditions, in the northern Hemisphere, has been an ongoing problem, recognized for decades. Are we witnessing a similar phenomenon on the southern tip of the continent?
Oh, pile on, Bill, by all means! To your point, I’d be cautious about our definition of “drought” and “desertification” as well. If the definitions are strictly about the amount of rain, that should track more closely with atmospheric changes. Therefore, that would be simpler (although by no means simple) to determine whether it relates to climate change. “Desertification” as a practical matter for people is more about the vegetation, though, which depends only in part on the precipitation. “Drought” can be defined as a lack of precipitation, but it’s *felt* as a lack of municipal water or a degraded agricultural yield. Now, it is true that an expanding subtropical high is is exactly the type of response that climate models have when perturbed with increased GHGs. Soeven if desertification is happening for other reasons, the climate change signal is expected to at least be an exacerbation of that desertification trend. I think that nuance is easy to lose when climate change has become such a buzzword for blame. I find it quite tricky because some consequences of climate change are (like sea level rise) both more clearly caused by climate change and also huge problems. But focusing on climate change for an issue like this drought might be a disservice because it distracts from more immediate socio-political issues.
I agree, Alex–we need to be careful how we use terms that have both technical and colloquial definitions, but this is a bar discussion, not one in the JGRA (or course, I have no idea who is reading this). I think my main point is that we are looking at an ecosystem that is demonstrably fragile in southern Africa, and the human footprint, whether from a longer-term, harder-to-quantify, imbalance of atmospheric gases (driving climate), or from a land-use-change that has occurred over a substantially shorter time frame, it’s still a uniquely (somewhat? largely? maybe?) manmade phenomenon. It may be impossible to differentiate amongst the two. I find myself wishing we had good satellite imagery of land use in Zimbabwe (and elsewhere in southern Africa) to see if, in parallel with large population increases, we have seen land use (and concomitant water use) changes, just as dramatic. My guess is yes, and we all know that land use changes can drive desertification. Add a little (technical) drought to the mix and, voilà….
Thank you for all your efforts–you put a lot of work into these posts (and responses, too), and…!