October 24, 2017

Climate change could spell disaster for coffee?

We seem to hear this scare at least once a year.  The truth is that coffee crops -- particularly the Arabica variety -- are quite sensitive to weather variations and do from time to time have "bad" years.  When that happens global warming is an easy culprit to blame. But there are problems with that:

All that global warming would do for ANY crop is to shift polewards the areas where it is grown.  There is no conceivable reason for a lasting shortage.  There are always new areas opening up for coffee growing anyway.

Secondly, coffee growers and regions would actually benefit from higher atmospheric CO2 levels. More CO2 stimulates plant growth and increases survival rates under drought and other adverse conditions.

Thirdly, if they understood any economics they would know that any lasting reduction in supply would cause price increases and sustained price increases would then draw out more supply.  Australia's "empty" North, for instance, could undoubtedly be opened up to coffee growing in some parts.  There is already a small operation on the Atherton Tableland.  They even grow Arabica there

Fourthly, you will note below that both drought and high rainfall are said to be bad for coffee growing.  Nice to have it both ways?


Centroamericano, a new variety of coffee plant, hasn’t sparked the buzz of, say, Starbucks’s latest novelty latte. But it may be the coolest thing in brewing: a tree that can withstand the effects of climate change.

Climate change could spell disaster for coffee, a crop that requires specific temperatures to flourish and that is highly sensitive to a range of pests. So scientists are racing to develop more tenacious strains of one of the world’s most beloved beverages.

In addition to Centroamericano, seven other new hybrid varieties are gradually trickling onto the market. And this summer, World Coffee Research – an industry-funded nonprofit group – kicked off field tests of 46 new varieties that it says will change coffee-growing as the world knows it.

“Coffee is not ready to adapt to climate change without help,” said Doug Welsh, the vice president and roastmaster of Peet’s Coffee, which has invested in WCR’s research.

Climate scientists say few coffee-growing regions will be spared the effects of climate change. Most of the world’s crop is cultivated around the equator, with the bulk coming from Brazil, Vietnam, Colombia, Indonesia and Ethiopia.

Rising temperatures are expected to shrink the available growing land in many of these countries, said Christian Bunn, a postdoctoral fellow at the International Center for Tropical Agriculture who has analyzed the shift in coffee regions. Warmer air essentially “chases” coffee up to cooler, higher altitudes – which are scarce in Brazil and Zimbabwe, among other coffee-growing countries.

Temperature is not climate change’s only projected impact in coffee-growing regions. Portions of Central America are expected to see greater rainfall and shorter dry seasons, which are needed to harvest and dry beans. In Peru, Ecuador and Colombia, rainfall is projected to decrease, potentially sparking dry periods.

These sorts of changes will pose problems for many crops. But coffee is particularly vulnerable, scientists say, because it has an unusually shallow gene pool. Only two species of coffee, arabica and robusta, are currently grown for human consumption. And farmers traditionally haven’t selected for diversity when breeding either plant – instead, essentially, they’ve been marrying generations of coffee with its close cousins.

As a result, there are precious few varieties of arabica that can grow in warmer or wetter conditions. In addition, diseases and pests that might be exacerbated under climate change could knock out entire fields of plants.

SOURCE






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