Thursday, August 10, 2017

The Russian Steppe 5: Climate

Our exploration of the Russian steppe began by setting the boundaries of both the Eurasian steppe in all its expanse and the Azov Uplands portion of the Pontic–Caspian Steppe (western steppe), in which Molotschna was located. We then turned our attention to key aspects of the steppe environment, beginning with the vegetation that characterized the steppe (feather grass) and the notable absence of trees across the gently rolling terrain. This post shifts to a second aspect of the steppe environment: climate, particularly as that relates to temperature and precipitation. 

Molotschna is frequently said to enjoy the “continental temperature pattern,” which apparently refers to the Köppen climate system of classification. Continental climates are typically affected by cold air masses from the north during the winter, leading to a coldest month with a mean temperature below freezing (26.6º Fahrenheit), and by warm air masses during the summer in which the temperature for at least four months averages at least 50º. 

Molotschna certain qualifies on both counts, as Staples explains: 

The continental temperature pattern in Molochna, with its moderate temperatures and long average growing season of 180 days is far kinder to agriculture than the precipitation pattern is. Even in the hottest months of June and July temperatures seldom climb above the low twenties (Celsius) [ca. 73º Fahrenheit], while the short mild winters mean that in most years livestock require fodder only from December to February, and some years it can graze on the steppe year-round. (Staples 2003, 8)

The figure below (see Staples 2003, 10) shows the range and average temperatures by month for the Molotschna village Ohrloff for the years 1841–1855. The temperatures are given in Celsius (left) and Fahrenheit (right). This chart clearly demonstrates the mildness of the typical climate of the area.


We should not, however, think of the weather as inevitably moderate. Staples adds: 

on occasion the prevailing winds blowing out of the east would bring with them their own unique hardships for settlers. In winter, fierce blizzards with high winds and killing cold sometimes swept across the steppe, decimating livestock herds. Summers could bring week-long windstorms—known to settlers as “black blizzards”—with hot, dry winds that stirred huge dust clouds and sucked the moisture from soil and plants, destroying unharvested crops, and sapping the nutritive value from fodder grasses. (Staples 2003, 9)

Another crucial element of the climate, especially for farmers, is precipitation: not only how much but also when it falls. Staples once again provides the details.

South of Molotschna, in the Azov Lowlands next to the Sea of Azov, the annual precipitation was 350–400 mm (13.8–15.7 inches). Further inland and higher, Molotschna averaged 400–450 mm (15.7–17.7 inches) of annual precipitation. Even so, Molotschna was on the border of being a sustainable location to raise crops. According to Staples, “most types of grain require at least 400 millimetres of annual precipitation” (2003, 6), which means that, on average, raising grain was possible; of course, some years would be below average, in which case one might expect crop failure.

Staples also notes that the timing of precipitation is key:

Even when precipitation was adequate it often failed to come at the time when it was most needed. Ideally, crops need water when they first germinate. In Molochna this means in March and April. However, recorded rainfall in this region was heavily concentrated in the months of May, June, and July. (2003, 7)

More precisely, 39 percent of the annual precipitation fell in the months of May, June, and July; only 12 percent fell during the crucial months of March and April (see Staples 2003, 8, fig. 1.2).

All these numbers are interesting, but they become even more meaningful when we compare them with corresponding statistics from central Nebraska. It is one thing to say that Molotschna temperatures were generally moderate and that the area received roughly 16–18 inches of precipitation each year. How does that compare to the averages for York, Nebraska? The figure below helps us make several comparisons.


1. Comparing the temperatures requires a little work, since the Molotschna figures were (apparently) the mean by month and the York ones are highs and lows by month. Nevertheless, averaging the York high and low for each month probably produces the same mean reflected in the Molotschna numbers (unless the Molotschna numbers were based on hourly readings).

So, for example, the January mean for Molotschna was 21º Fahrenheit, while for York it is 24. There is no need to give all the numbers, since they track fairly closely with the January spread. On average, York is several degrees warmer than Molotschna, although one should note that the spread is the greatest in the summer months of June–September.

2. Precipitation is where the real difference lies. According to the U.S. Climate Data website (here; also the source of the figure above), York receives an average of 30.25 inches of precipitation, which is nearly double the Molotschna average. Further, whereas Molotschna averaged only slightly less than 2 inches of rain in the months of March and April, York enjoys over 5 inches of rain during the same months.

3. One final comparison point is interesting, although not entirely clear. As noted above, the average growing season for Molotschna was 180 days. Generally growing season is defined as “continuous temperatures > 32 F, following the last freeze in Spring and prior to the first freeze in the Autumn” (see the UNL website here). According to the website just referenced, the average growing season for Lincoln, Nebraska, is 162 days, which is substantially shorter than Molotschna.

If the 180 and 162 figures are counting the same thing, one might reasonably conclude that central Nebraska has a shorter average growing period due to its temperature extremes (later frosts in the spring and earlier in the fall) but that, on average, Nebraska enjoys superior growing conditions (warmer temperatures and greater precipitation) than Molotschna. Whether that superiority carries over into the final element to consider (soil) remains to be seen.

One final point before we end this post: one cannot miss the significant degree of similarity between Molotschna and central Nebraska. Not only did both exist as steppe land, or prairie (which is another word for steppe), but they were remarkably similar in climate, at least in terms of temperature. In other words, although our family traveled thousands of miles to start a new life in central Nebraska, the place where they settled had to remind them more than a little of the home they had left behind.


Work Cited

Staples, John R. 2003. Cross-Cultural Encounters on the Ukrainian Steppe: Settling the Molochna Basin, 1783–1861. Tsarist and Soviet Mennonite Studies. Toronto: University of Toronto Press. 



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