Map and climate data. (a) Map showing the PreBalkhash plague focus (1) and other locations mentioned in the text: the Almaty hospital (2); Lake Issyk-Kul (3); the city of Constantinople (4); the city of Caffa (5); the Yunnan province (6); the areas containing the dendrochronological sites (T) (7); the Guliya glacier (G) (8); and Wanxiang Cave (S) (9). (b) The climate proxy time series. For T and S the green and black lines respectively represent 10-year moving averages, for G the red line is the decadal reconstruction, while the blue line is the annual series (c) Average (Mar-Oct) NDVI for East Asia. Black contour lines correspond to interannual variability as shown in (d), which represent the standard deviation of the annual mean for each pixel. We see that the most green (coastline broadleaf) and most dry (arid grass/shrubland) regions tend to have the least annual variability. Black contours indicate the mean.