Page 243 - Climate Change and Food Systems

chapter 7: grain rain production trends in russia, ukraine and kazakhstan in the context of climate change and international trade
increasing greenhouse gas concentrations.
The climate modelling scenarios suggest that, compared with the late Soviet Union period of the 1980s, the temperature in the grain-producing areas of the Russian Federation, Ukraine and Kazakhstan will increase by 1.5-1.8 oC by the 2020s and by 2.2-3.9 oC by the 2050s, with the greatest increase in winter (Mitchell et al., 2002; Lioubimtseva and Henebry, 2009; 2012; Dronin and Kirilenko, 2013). Despite significant differences in the range of changes among the scenarios produced by different models, most studies tend to agree that summer precipitation is likely to decline all over the region and winter precipitation is projected to increase in parts of Western
Russia and Siberia (Dronin and Kirilenko, 2008; Lioubimtseva and Henebry, 2012).
In order to evaluate impacts of climate change on the grain belt of Central Eurasia, we have computed the twentieth century temperature
and precipitation trends for Kazakhstan, the Russian Federation and Ukraine by fitting a
linear regression model to the 1901-2000
mean temperature and precipitation of these
three countries. The historical climate data for
the countries were retrieved from University
of Eastern Anglia’s Tyndall Centre for Climate Change Research (TYN) country average (CY) database 1.1 (Mitchell et al., 2003). Temperature trends are similar for the Russian Federation and Ukraine (0.08 ˚C/decade), with a higher trend in Kazakhstan (0.14 ˚C/decade). These changes were accompanied by precipitation increases of 0.7, 4.6 and 3.5 mm/decade in Kazakhstan, the Russian Federation and Ukraine, respectively. Over the
last three decades of the twentieth century, these changes accelerated, with the temperature trend increasing to 0.37 ˚C/decade in Kazakhstan, 0.32 ˚C/decade in the Russian Federation and 0.23 ˚C/ decade in Ukraine, with higher changes in winter (1.30, 0.81 and 0.73 ˚C/decade, respectively) and considerably lower warming in summer (0.33,
0.25 and 0.35 ˚C/decade, respectively). During
the last three decades of the twentieth century,
the increasing precipitation trend continued in Kazakhstan (2.1 mm/decade) and the Russian
Federation (2.8 mm/decade), but was reversed in Ukraine (-3.7 mm/decade). While in Kazakhstan, summer precipitation has increased, in Ukraine and the Russian Federation it has declined.
Observed trends exhibit a high level of
spatial heterogeneity, especially in the Russian Federation. While on average the temperatures have become 1.29 ˚C warmer over the past
100 years (1907-2006 – compared with 0.74˚ C global warming over the same period) (National communication, the Russian Federation, 2010),
the warming trend was higher in Eastern Siberia and in the north of the European part of the country, with lesser warming in the intensive agriculture zone located in the south of the European part of the Russian Federation (NOAA GISS Surface Temperature Analysis, http://data. giss.nasa.gov/gistemp/). Similarly, the highest changes in precipitation were observed in the eastern part of the country in the spring season. There is considerable uncertainty in the data on precipitation trends, especially over the entire twentieth century, due to low density of the observational network (National communication, the Russian Federation 2010). In the agricultural region of northern Kazakhstan, the warming
trend is higher compared with the entire country, especially in winter, and is accompanied by increasing winter and decreasing summer precipitation (National communication, Kazakhstan, 2009). Higher temperatures lead to a greater effective temperature sum (ETS, measured
as a sum of growing-degree days with base temperature of 10 ˚C), a longer vegetative period, and to shifts in phenology. In extra-tropical regions, multiple studies demonstrated a lengthening of
the growing season by approximately 10-20 days in the last few decades, mostly as the result of
an earlier spring (Linderholm, 2006). In Europe,
the growing season has extended by 3.5 days/˚C over the last 30 years of the twentieth century (Menzel et al,. 2006). In the principal agricultural areas of the Russian Federation, the length of the period with temperatures above 10 ˚C (associated with the growing period) was increasing by 2.3-2.7 days per decade in central Chernozem, northern
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