Temperature and water and tea

No, this isn’t an article about brewing temperature and water (could write a bundle about that, and may do so at another time) — it’s about world temperatures this July, and precipitation patterns. Here’s the map of July 2016 temperatures from the National Oceanic and Atmospheric Administration (NOAA):

See all that salmon color? (Grey is for areas with no data). It’s been hot hot hot. When I was staying with my daughter in Massachusetts for the month of July, we had cabin fever in reverse.* It was just too hot to run around in the yard or anywhere outdoors. And dry, too—my son-in-law was kinda happy he didn’t have to do any mowing.

Now look at southern China. “Record Warmest” just where some of my favorite teas are grown. Quite warm in the tea growing areas of India as well, and Kenya was pretty hot, too.  

According to World Tea Expo speaker and friend Selena Ahmed,** the increased heat led to early budding of tea in Zhejiang. When the early budding is followed by a frost, which it was this past winter in the home of Longjing/Dragon Well tea, yields go down dramatically. ***

It’s not just the heat, though, it’s also the increased precipitation. To quote Selena: “For tea, when there’s too much rain, there’s a dilution effect of the secondary metabolites.” Those wonderful flavor compounds that make a superb oolong? They’re all secondary metabolites!

Look for the red box — I've circled the tea growing areas affected by increased precipitation this winter in the NOAA map below—yep, there’s a blue dot near where my beloved oolongs grow:

What to do? Selena offers some suggestions in the eater.com article, prominent among which is the creation of a diverse ecosystem, where plants can in essence protect each other, as the ancient tea trees in forests did.*** 

Another suggestion that has been made: switching from making green tea and oolong to making black teas, where the more thorough oxidation leads to a relative increase in secondary metabolite production…but then with oxidation you lose all the “green” flavor metabolites that make a Longjing or an oolong so exquisite. 

So all I can say right now is, reduce your carbon footprint however you can, and enjoy your tea for the treasure it is.

*For those of you who haven’t experienced it, cabin fever is the ennui you develop when you are cooped up at home and can’t leave due to snow piled up outside.

** Selena Ahmed is Assistant Professor of Sustainable Food Systems at Montana State University, Bozeman.

*** http://www.eater.com/drinks/2016/7/8/12111038/climate-change-tea-leaves-flavor

**** Here’s an article (it’s available to all)  by Selena and her colleagues about modeling climate change— the change will lead to lower yields, which will especially hurt the small farmer:  Boehm, R.; Cash, S.B.; Anderson, B.T.; Ahmed, S.; Griffin, T.S.; Robbat, A.; Stepp, J.R.; Han, W.; Hazel, M.; Orians, C.M. Association between Empirically Estimated Monsoon Dynamics and Other Weather Factors and Historical Tea Yields in China: Results from a Yield Response Model. Climate 2016, 4, 20. http://www.mdpi.com/2225-1154/4/2/20