Samuel Cohn: Global Social Trends

We all know that global warming is bad because it has disastrous ecological consequences.

    

The seas rise up, destroying coastal cities.

    

Giant storms wreak havoc everywhere.

    

Unseasonable heat or unseasonable cold wrecks agriculture, overwhelms energy grids, melts the polar ice caps, and destroys all sorts of species.

    

One of those species might be humans.

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The long term effects of global warming are up for debate.

    

However, there is now hard evidence that the climactic shocks associated with global warming are increasing global poverty right now. Carlo Azzarri and Sara Signorelli have published an excellent article in World Development (2020) “Climate and Poverty in Africa South of the Sahara” that demonstrates in concrete terms the effect that climate shocks are having on standards of living in Sub-Saharan Africa. Adverse climactic trends are increasing poverty and lowering food consumption.

    

Climactic change represents different kinds of threats for different ecosystems. For lowland coastal areas, a primary concern is flooding. Some island nations, such as Kiribati or the Maldives, would completely disappear if sea levels rise. Other countries with dense coastal populations, such as Bangladesh, would lose territory that represents the home of a vast proportion of their people, plus the basis for much of their agriculture.

    

In most of Sub-Saharan Africa, the issue is water scarcity rather than flooding. Higher global temperatures alter weather patterns, generally reducing rainfall and increasing drought. Higher global temperatures also affect the viability of agriculture simply by exposing many crops to more heat than is optimal for survivability and growth. Higher temperatures also increase the rapidity of water evaporation. Even with the same amount of rain, higher temperatures can mean more drought because less water gets absorbed into the soil.

   

On this basis, the climate trends for Sub-Saharan Africa have been highly adverse. Rainfall has declined steadily from 1950-2010. Mean temperatures have risen for the same period. A sophisticated measure of available water in the soil, SPEI (the Standardized Precipitation Evapotranspiration Index) also shows adverse trends although these have been less severe.

   

What are the effects of all of this on poverty and food consumption? Azzari and Signorelli examined household consumption data for families in 24 different Sub-Saharan African nations. They considered three measures of family well-being, money spent on consumption, money spent on food, and incomes below the poverty line. All three measures show similar results.

 

1. The more water available in the soil (SPEI), the greater the food consumption and the lower the poverty rate.

 

2. Flooding lowers food consumption and increases the poverty rate. Irregular rain can be just as bad as absence of rain.

 

3. Droughts lower food consumption and increase the poverty rate. (There were a few equations where this did not work out.)

 

4. Higher temperatures lower food consumption and increase the poverty rate.

 

5. Temperature heat shocks (periods of significantly higher temperatures than is normal for a region) lower food consumption and increase the poverty rate.

 

6. Money surprisingly does not cushion against these climactic effects. Households with high assets were as hurt by the adverse rain and temperature effects as households with low or no assets. The damage they suffered was smaller. Typically a farmer with large holdings only suffered half of the effects of drought or floods that were experienced by small holders. But bad weather lowered the standards of living of the rich as well as the poor.

 

7. Women, the less educated and people with larger families had lower food consumption and a higher poverty rate. This is standard knowledge in the study of African poverty. However, neither being male, having an education nor having a small family shelters from the effects of climate.

 

8. Urban populations are just as adversely affected as rural populations. Urban populations are dependent on the agricultural sector for their food supply. When climactic change reduces crop yields, food becomes scarce. The urban poor experience the effects of temperature or floods as food becomes more expensive in their local stores – making it harder for them to feed their families.  

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In the United States, we worry about what climactic change will do to our future. The present-day victims of climate change are generally residents of coastal areas who are at greater risk of hurricanes and other forms of natural disaster.

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In Africa, the adverse effects of climate change are far more widespread. Hotter temperatures and disrupted rainfalls produce poverty and food deprivation now.

    

In America, we worry about whether addressing climate change will adversely affect economic growth.

   

In Africa, economic growth is being limited by climate change right now. Agriculture is being disrupted. Poverty is increasing. Rising poverty in and of itself can reduce economic growth. Poverty lowers consumption, lowers market demand for goods and services and in and of itself decreases employment. African economies need their customers to have money in their pockets so that they buy products from African firms. If people are too poor to buy food, they are also too poor to buy much of anything else.

   

Reducing global warming raises the standard of living for some of the poorest populations on our planet. That is another fine reason to start reducing global warming now.

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