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A lot of us rely on a morning cup of coffee,  or several morning cups of  coffee, to get us going.  But the taste and the quality of that  coffee might not stay the same forever.  Climate change has the potential to not only shift  where and how we grow coffee in the future,  but affect whether it can be grown at all.  Whether you’re a coffee aficionado who  obsesses over acidity, aroma, and brew method,  or you hastily chug some  corner-store instant blend on the go,  climate change means bad news for your beans. There are lots of different blends and styles of   coffee, but we usually just drink two types.

The most famous is Coffea arabica.  The other is its less celebrated cousin  Coffea canephora, also known as Robusta.  Most of us sip Arabica for our daily cup of Joe. But if you get your fix from instant coffee,   it’s probably Robusta, which is not considered quite as tasty.  The Arabica coffee plant is pretty particular. It grows best in wet and cool mountain regions.  Unfortunately for Arabica,  and for us, climate change  is bringing a slew of problems to those  higher-altitude coffee-growing areas.  That’s especially true in places  where Arabica coffee grows wild, .

In the humid, shady mountain  forests of Ethiopia and South Sudan.  The genetic diversity found in  these wild plants might hold the key  to making coffee more resilient to  climate and disease in the future.  But climate change is increasing temperatures and shortening wet seasons in these areas.  That makes the outlook not so  good for wild coffee forests.  By 2088, we could see a 50-80%  drop in Arabica populations,  which could be enough to land  them on the endangered list.  Combine that with deforestation, and this special species of bean   could be at greater risk of extinction. While Robusta is definitely more,   well, robust when it comes  to environmental changes,  climate change is shrinking its  available growing range too.  And as temperatures rise, both  species are being hit harder by pests,  like the coffee berry borer. This species of bark beetle is   a serious enemy of coffee plants.

It used to attack only plants growing   below certain elevations. That minimized its impact,   since coffee is grown at high altitudes. But with hotter weather, this beetle is   expanding its range into higher ground, and appearing in coffee plantations.  Warmer weather is also encouraging  a number of fungus species  to move into Arabica and Robusta territory.

One of the most notorious is coffee rust,   which turns the leaves a rusty orange. When coffee rust arrived in   Sri Lanka in the 19th century, it wiped out the entire industry in ten years.  Coffee rust also followed the coffee  industry to Central and South America,  where higher heat and humidity due to climate  change made plantations vulnerable to infections.  In a short time, the fungus caused billions  of dollars in damage and lost profits.  And because climate change is  shrinking coffee-growing habitat,  there are fewer places left for coffee growers  to flee this fungus, and other diseases.  Even if we can keep farming Arabica in the future, lower quality growing environments   might negatively impact flavor, literally leaving a bitter taste in your mouth.  The amount of shade and  differences in microclimates  change the look, smell and taste of coffee beans. The best specialty coffee comes from natural,   shady coffee-producing forests, since Arabica grown under high sun   exposure takes a hit in terms of bean quality.

Also, in healthy coffee-producing forests,  higher diversity in insect and orchid species  appears to play a role in coffee quality.  In fact, coffee connoisseurs can  differentiate between coffees  grown in different elevations and conditions, sort of like how some sommeliers can   taste variations in wine. And the bad news for beans   isn’t just a downer for coffee snobs. Climate change is expected to make a dent   all across this multi-billion-dollar sector, and on the hundred million coffee farmers   around the world.

But there is some hope!  Researchers are looking into other coffee species that might be more resilient   than Arabica and Robusta. In fact, there are 124 known wild   coffee species growing across the world, from tropical Africa to Australasia.  And many are already used locally  to make a morning cup of Joe.  One especially promising  species is Coffea stenophylla.  This bean tastes similar to Arabica – and  it can be grown at higher temperatures!  Stenophylla and a number of other wild species have important characteristics related to heat,   drought, pest and disease tolerance. Unfortunately, 60% of all wild coffee   species could also be at risk of extinction.

That’s mainly because we’re destroying the   forests where they are found, to make room for agriculture,   livestock farming, and new settlements. In addition, some wild species are   found in high-conflict regions, which presents additional challenges.  So, even though many of us take for granted that coffee is a reliable part of our day,   it may not be in the future. As if we needed another reason   to get serious about climate change.

Thanks for watching this episode of SciShow,  and thanks as always to our patrons  for helping us make it happen.  We cannot buy you a coffee to say thanks,  but we do have some neat perks available,  like our new behind-the-scenes podcast. If you’re interested, you can get started   at patreon.com/scishow. [♪ OUTRO].