Climate

“Climate” refers to the average weather conditions found over large territories. Climate is expressed in terms of daily, monthly, and annual values of air temperature and precipitation, as well as wind speed, moisture, seasonality, and other factors averaged over a standard period of observations, usually 30 years. Climates of the world are differentiated into five broad types, labeled with the letters A through E; this typology is known as the “Koppen system.” A-type climates are tropical and are not found in the countries of the former Soviet Union (FSU). B-type climates are dry climates and are very common in much of Central Asia, Kazakhstan, southern Ukraine, and parts of Russia, just as they are in the western United States or the Middle East. C-type climates are mild, without much frost in winter. These gave rise to some of the earliest human civilizations and are generally considered pleasant (think of places like coastal California, Italy, or Japan). In Northern Eurasia, they are found only in small areas, mainly along
the Black and the Caspian Sea.

The most common climate type in the FSU—covering much of Russia and good portions of Ukraine, Belarus, and Kazakhstan—is the D type. This is a microthermal climate of continental interiors. It features four seasons, including a distinctly cold winter; “cold” in this context requires the average monthly temperature to go below freezing. Some locations with this climate have average winter temperatures below –40?C in the coldest month, although a typical winter would be 3–5 months long with temperatures in the –10 to –15?C range. Most of Canada, Alaska, the upper Midwest in the United States, and Scandinavia have climates of this type. Can there be an even colder climate? Yes: The E type is the coldest, a true polar climate present on 10% of Russia's territory. Each of these broad climate types in turn has subtypes. For example, the climate of much of Moldova (or Peoria, Illinois) is the Dfa subtype, while the climate of Moscow (or Minneapolis, Minnesota) is the Dfb subtype. The main difference between them is how warm the summer gets—above or below +22?C on average, respectively. The letter f means that there is sufficient moisture year round.

What Factors Create a Particular Type of Climate?

Why are Moscow winters not like those in Baku? Why is much of Central Asia so dry? Why can people in Georgia grow tangerines, while people at exactly the same latitude in Vladivostok cannot? Why is northern European Russia fairly cold in winter, while eastern Siberia is mind numbingly cold? Such questions arise when we try to understand the spatial patterns of climate distribution.

Climatologists generally consider the following factors important in producing a particular climate type:

  • Latitude, or distance from the Equator. The farther a place is from the Equator, the less direct sunshine is available. All of Northern Eurasia lies far outside the tropics, north of 36?N; in comparison, southern Florida is at 25?N.
  • Elevation above sea level. The higher this elevation is, the colder the climate gets. Some of the highest peaks in the FSU are over 7,000 m.
  • Proximity to the ocean. Water cools down and heats up very slowly, thus reducing the differences between seasons in coastal locations; far inland, the seasonality is much greater. In Northern Eurasia, the inland effect is most pronounced in northeastern Siberia.
  • Presence of ocean currents. Cold currents make coastal locations cool and dry; warm currents make them warm and wet.
  • Prevalent wind direction. Over much of North America and Eurasia, the winds in the middle latitudes generally blow from the west, following the rotation of the earth.
  • Position relative to a mountain range. Windward locations get orographic precipitation; leeward locations get almost no rain (the so called rain shadow effect). Mountains may protect a city from cold northern winds, or expose it to dry and warm catabatic winds rushing down the slope.
  • Cloud cover and dust. These may vary, depending on local natural or anthropogenic conditions, thus attenuating the climate.
  • Human infrastructure. This may create a local “heat island” effect; the downtown areas of major cities are typically a few degrees warmer than the surrounding countryside.
  • Global climate change. Increasingly, this is being driven by human-made emissions of greenhouse gases.

Two of the most striking things about Northern Eurasia in general, and Russia in particular, are how big and how northern this area generally is. Russia is located in the northern part of the biggest landmass on the planet, considerably north of the continental United States. The southernmost point of the region, Kushka in Turkmenistan at 36?N, still lies far north of the Tropic of Cancer (23.5?N). Thus we may expect winters to be generally very cold in the region, because of both its latitudinal position and a lack of moisture in much of the interior. Although Antarctica gets even colder, the cities of Oimyakon and Verkhoyansk in Yakutia hold the world record for the greatest temperature difference between summer and winter (55?C on average) and for the coldest spots in the Northern Hemisphere (–72?C vs. –65?C in parts of northwestern Canada).

Another prediction we may make is that because much of Russia is flat, the climate will not be greatly modified by mountains. Mountains, of course, do modify the climate of the Caucasus and Central Asia, but much of European Russia and Siberia have uniform climate conditions over large swaths of terrain. The climate zones pretty much run in parallel zones from west to east, in the following very predictable order from north to south: polar, tundra, subarctic, cold continental, semi-arid (steppe), and arid (desert), with a few pockets of subtropical climates in the extreme south. This phenomenon was noticed as early as the mid-19th century and was used by Vasily Dokuchaev, the founder of modern soil science, to predict the distribution of Northern Eurasian soil and vegetation zones in accordance with the “law of natural zonation.”

Oceans play only a minimal role in forming the climates of Northern Eurasia, because they are too far away from most areas. The Arctic Ocean is frozen along most of the coast for about 6 months every year, thus climatically acting as a big snow field that gives no moisture to the interior. The Atlantic Ocean does have a strong moderating effect on the Kola Peninsula and the Baltic states (as it does on Europe), keeping them warmer than they should be, given their latitude. The Pacific Ocean has an influence on the extreme southeastern corner of Russia by bringing in monsoons and occasional typhoons, but during much of the year the winds in Siberia blow from the west (i.e., offshore), and again little moisture comes from the ocean to the land.

So, broadly speaking, Northern Eurasia has four major climate types. If we return to the Koppen classification system, these are as follows:

  • Polar, or arctic climates of deserts and tundras (EF, ET).
  • Subarctic climates of the boreal zone, where coniferous trees are common (Dc, Dw).
  • Temperate climates, where either deciduous trees or steppes developed, depending on the availability of moisture (Dfa, Bs).
  • Subtropical climates, where no freezing is observed in winter (Cs, Ca), or warm deserts (BW). There are no A-type tropical climates at all.

Climates at Different Destinations

To give us a clearer idea of what climates are like in different zones, let us take an imaginary trip to a few selected destinations in Northern Eurasia. We will visit places in each of the major climate types, learn what the climates are like there, and try to imagine what we would need to consider when packing for the trip.

To interpret the climate at each site, let us use climate diagram. Such a diagram summarizes both average monthly temperature and precipitation in one easy-to-understand graph. The horizontal axis shows months, arranged from January to December. The vertical axis represents temperature, and the bars represent precipitation. Also shown are latitude, longitude, elevation above sea level, the mean annual temperature (MAT), and the mean annual precipitation (MAP). The diagrams are scaled to
have a bioclimatic meaning: Each 10?C gradation corresponds to 20 mm of monthly precipitation. At this scale, when the temperature curve rises above the precipitation curve, a moisture deficit is likely, and this will have a negative impact on plants.

Let's imagine traveling on a chartered plane, leaving Chicago and heading straight up north across the North Pole to the Novaya Zemlya islands in Russia. How long do you think it will take us to get there? 20 hours? In fact, the distance of 6,700 km can be covered in about 8 hours in a modern jet—less time than it takes to reach Paris! Our first stop is on the North Island of Novaya Zemlya, which is mainly covered with ice and snow. There is no permanent human settlement, and of course no big airport. Let's hope our imaginary plane can land on top of the ice cap near Mys Zhelaniya (the Cape of Desire). The climate here is similar to parts of Greenland or northern Iceland. It is a polar climate (E type), with temperatures near or below freezing all year (MAT= –9.7?C), and intermediate precipitation (MAP = 527 mm). Some parts of the eastern Arctic in this zone are much drier. For example, Wrangel Island in the East Siberian Sea gets only 300 mm of precipitation, almost as little as in a desert.

What matters the most to plants here is the length of the growing season, however, when temperatures rise above freezing: It is very short, just a few weeks in July and August. Only a handful of the hardiest species of plants (mainly lichens, mosses, and some Arctic grasses) can grow locally. No plant life exists on the ice cap itself. The North Island would be a tough place to spend even summer, let alone winter. Its analogues in North America include islands in the Canadian Arctic, although these tend to be drier than Novaya Zemlya (MAP = under 200 mm). You would need high-quality winter gear during most of the year. The presence of the ocean, however, modifies seasonality a bit; the coldest temperatures recorded at Mys Zhelaniya are “only” in the low –40?C, not –60?C as in Siberia. Even in July, though, temperatures do not rise above +10?C.

Our next stop, 1,100 km to the southwest, takes us to the tundra—still within the polar climate type (the subtype is ET). A good example would be the city of Naryan-Mar, Russia, where the Pechora River flows into the Barents Sea. The temperature here is a bit warmer (–3.5?C), but precipitation is about the same (468 mm). The growing season is longer, about 3.5 months. Winters are long and dark, because this area is still above the Arctic Circle. Snow stays on the ground for 220 days. Trees normally do not grow in the tundra, because they do not get enough warmth in the summer months to develop fully. Grasses, sedges, mosses, and small shrubs are best adapted for this climate type. You would still need a nice winter outfit during much of the year in Naryan-Mar. The coldest temperatures here are about –50?C, while the warmest may top +30?C in the summertime. More typical are cool summers (about 15?C in the middle of July). Nome, Alaska, has a pretty similar climate. Naryan-Mar is a fascinating place to visit, but not an easy place to stay over winter.

Our next stop will be in a D-type climate. Dtype climates are the most widespread in Russia, covering over 80% of its territory. The air temperature in the coldest month is always below freezing, but the warmest month is generally above +10?C. Three distinct subtypes of the D climate type exist in Russia: subarctic Dfc (northern European Russia and western Siberia); subarctic with dry winter, or Dw (much of eastern Siberia); and the milder humid continental Dfb (central European Russia, including Moscow). Our subarctic stop in the European part will be in the city of Syktyvkar (MAT = +0.3?C, MAP = 492 mm). The growing season here is longer than in the tundra, between 5 and 6 months, with snow staying on the ground “only” 180 days. Trees can grow here. Most of these are pine, spruce, and fir—conifers whose needles are available yearround for photosynthesis, to compensate for the still relatively short growing season. The winters remain cold (–51?C is the record low), but summers can be surprisingly hot (+35?C is the record high). There is ample year-round precipitation. Dawson Creek, British Columbia, has a broadly similar climate, with a longer vegetative season of almost 8 months.

Minneapolis, Minnesota, and Moscow, Russia, can both be used as examples of the humid continental microthermal climate (subtype Dfb). This climate is warmer than the subarctic, but it still has a distinct, cold winter, with the average temperature below freezing. Summers are warm, but almost never hot. Moscow (MAT = +3.6?C, MAP = 575 mm) has moderately cold winters, with temperatures in January averaging about –10.3?C, and moderately warm summers, with July temperatures averaging +17.8?C. The coldest temperature ever recorded is –42?C, and the warmest temperature is +37?C. There are four distinct seasons, with winter lasting about 5 months. The Minneapolis climate is very similar (MAT = +6.6?C, MAP = 631 mm), with slightly warmer summers (+22.8?C average in July, –10.9?C in January). The primary difference between the two is the amount of available daylight in summer versus winter: Minneapolis is located much farther to the south (44?N vs. 56?N for Moscow), and thus has shorter days in summer, but longer days in winter. There are also more cloudy days in Moscow, in part because of its proximity to the Atlantic and in part because of the air pollution. Moscow's industries generate a lot of dust, which causes rain droplets to form. The city's actual temperatures are about 2–3?C higher in winter than in the surrounding countryside. When is the best time to visit Moscow? My personal recommendation is either the late spring (May), when flowers are in bloom and nightingales are singing in the city parks, or the midautumn (early October), when it is still relatively warm and all the leaves are at their peak color.

South of Moscow, we quickly enter dryer climates belonging to the B type. Notice that there is no C type between B and D. B-type climates are arid or semi-arid. Their exact classification is complex, but generally these climates have a moisture deficit at least part of the year. When there is not enough rain, but plenty of warmth, potential evaporation exceeds available precipitation, and a moisture deficit results. As noted earlier, we can see when that happens on the climate diagrams, whenever the temperature curve goes above the precipitation curve. Volgograd, the famous Stalingrad of World War II, is located in the semi-arid BSk climate (MAT= +7.7?C, MAP = 345 mm). An analogous climate in North America would be found near Pierre, South Dakota. For about 4 months in the summer, there is a moisture deficit. In midsummer in Volgograd, temperatures can be as high as +42?C (average about +24?C), while precipitation is scarce (22 mm per month, compared to 74 mm in Moscow). The plants best adapted to this climate are grasses and some long rooted perennial forbs—in other words, prairie plants. In Eurasia, such grasslands are called “steppes.” Steppes are semi-arid, meaning that the moisture deficit lasts only a portion of the entire year. Trees do not grow well in this type of climate. The winters can be still very cold (absolute minimum = –35?C) and windy, as the Nazi army fully experienced when it was trapped in November 1942 near Stalingrad. The snow stays on the ground for about 80 days a year.

True deserts are found in a small section of Russia next to the Caspian Sea in Kalmykia (this is the only desert in Europe, in fact), as well as in southern Kazakhstan, Uzbekistan, and Turkmenistan. The capital of Turkmenistan, Ashgabat (MAT = +16.9?C, MAP = 193 mm), has a typical desert climate (BW). Virtually no rain falls in summer, and, unlike in the U.S. Southwest, there is no August monsoonal rain. The peak of precipitation occurs in spring, when 35–45 mm of rain may fall per month, instantly turning the gray desert into a flowering garden. Winter temperatures on average do not drop below freezing (average January temperature = +4.7?C), and the summers are uncomfortably hot (+37?C is typical). Las Vegas, Nevada, has a similar climate, except that it is even drier (100 mm of precipitation per year vs. 193 mm in Ashgabat) and a bit warmer in winter.

If you live in the southeastern United States or in California, you may be wondering by now whether there are any climates in the FSU that would match yours. Specifically, such C-type climates are only found in Moldova; in the extreme southern part of Ukraine (Odessa), especially the southern portion of the Crimea near Yalta; and in narrow strips along the Black Sea in Russia and Georgia, and along the Caspian Sea. The warmest among these places is Batumi, a seaport in southwestern Georgia on the border with Turkey. This city is in a true subtropical climate (Ca), where many plants from Southeast Asia and Africa can survive winters. A famous Russian botanist, A. N. Krasnov (1862–1914), took advantage of this when he helped to establish a beautiful botanical garden in the city, full of exotic tropical trees and shrubs. In C climates, temperatures in the coldest month do not drop below freezing. This is extremely important to many plants (e.g., bananas or palms) that cannot tolerate even a short period of frost. The Crimea Peninsula and the Caspian Sea coast are relatively dry due to the mountain “rain shadow” effect, while the Black Sea coast is more humid. In a sense, the climate of the southern Crimea resembles that of the California coast, while areas near Sochi, Russia, feel more like the southeastern United States. However, Sochi's temperature and humidity levels are quite a bit below Florida's levels.

We have now completed our north-to-south transect. If we were to fly farther east (to Yakutsk and beyond), the climate would get on average much colder and dryer than in most of the European part of the FSU. The extreme Far East experiences monsoonal influence in later summer, and an occasional typhoon or two. Winters there are not as cold as in Siberia, but heavy wet snow is very common, while summers are moderately warm and muggy.

Human Adaptations

Much has been written about the brutality of the Russian winters. Of course, the cultures of Russia developed in them and with them. The indigenous peoples of Siberia experience even colder average conditions than those of the Russian core. Parts of the Central Asian deserts may be very hot and dry in summer, but frigid in winter. Coastal St. Petersburg is foggy and cool year-round, and very dark in winter; it is located at the same latitude as Anchorage, Alaska, after all. Murmansk is a city of 300,000 people located at the latitude of Barrow, Alaska (population 4,000). The sun does not rise above the horizon there for about 1 month each winter, so people often get depressed and have to be treated in sun rooms.

Obviously, all cultures of the FSU have had to learn to live with the climate, whatever it might be. Here just a few interesting cultural adaptations to climate are briefly mentioned.

  • Traditional Russian peasant homes (izba) were one- to two-room log cabins, with a massive brick oven occupying about one-quarter of each home's interior space. The oven was stocked with wood. Peasants would not only cook in the oven, but sleep on its top.
  • In northern Russia, farm animals would be kept indoors in a covered area adjacent to the main house, to save heat and to keep the animals warm.
  • Much of the traditional dress is winter gear: valenki (felt boots with rubber bottoms), tulup (an overcoat made of sheepskin), and ushanka (a fur hat with ear flaps). Women have also made ample use of woolen scarves and shawls.
  • Typical Russian food is heavy on fat and carbohydrates to provide much-needed calories in winter. However, two long fasts (one before Christmas and one before Easter) were also traditionally observed, when no animal products could be eaten. This reduced the amount of meat that had to be raised, but it also meant that the need for more fat and protein went unmet for lengthy periods.
  • Only hot tea is drunk in northern Russia. Ice is never put in beverages.
  • The calendar of feasts in the Russian Orthodox Church is busier in winter and freer in summer, to allow for ample time in the fields during the short growing season.
  • Conversely, in the warmer climates of Central Asia, homes are constructed to keep the heat out, commonly with whitewashed walls, small windows, and good ventilation; people sit on low furniture or cushions spread on the floor to enjoy cooler air.
  • In Central Asia, heads are always protected from the sun by a variety of creative headgear (e.g., tyubeteika hats for men and scarves for women).
  • Central Asian cultures take a long midday break from work to avoid heat (similar to the Spanish siesta).

The traditional cultures of Northern Eurasia evolved many other unique adaptations to their particular environments. Two sets of these adaptations are described in greater detail in Vignettes 3.1 and 3.2). However, now all cultures are threatened by the increase in the rate of global climate change.

The Effects of Climate Change

Climate is always changing naturally. Seventy million years ago, there were no ice sheets anywhere in the world; palms were growing in Greenland, and dinosaurs roamed the earth. Conversely, just 20,000 years ago, the earth was in the grip of the last full Ice Age; ice sheets extended into Iowa in North America and Ukraine in Eurasia; and the woolly mammoth was the largest animal. In the past 150 years, however, the natural pace of change (mostly apparent as a warming trend) has greatly accelerated, due to human impact on the makeup of the atmosphere. The human role in global climate change is no longer contested in reputable scientific circles (although it may be by certain political groups). Al Gore's documentary An Inconvenient Truth won him a share of the Nobel Peace Prize in 2007. In the same year, the other winner, the Intergovernmental Panel on Climate Change (IPCC), released a new cache of global reports suggesting that the rest of the 21st century will see a much warmer climate. Not only is the climate warming up; it is virtually certain that it will continue to do so at increasing speed and with poorly anticipated consequences.

Generally speaking, Russia has relatively little cause for concern compared to its coastal European neighbors (especially the Netherlands and Denmark) or its southern Asian neighbors (Bangladesh, the Maldives). According to the IPCC, the two main impacts of the future climate change will be (1) rising sea levels and submergence of the coasts, especially if and when the western Greenland ice sheet melts; and (2) warmer temperatures, especially in the Arctic and especially during winter nights, which may lead to moisture deficits in many areas because of less snow cover. On the first count, Russia has few seaports to worry about, and its capital and biggest city is far inland at a comfortable 156 m above sea level. Only a fraction of the Russian population (8%) lives near a seacoast. The main urban area that will be affected is St. Petersburg, which is right at sea level and is commonly flooded by the spring meltwater from the Neva. Compare this to the United States, where two-thirds of all people live within 200 km of a coast, and where the two biggest urban areas (the New York City and Los Angeles areas) are right at sea level.

The Central Asian states of the FSU have no oceanic coastline at all. The Caspian Sea is actually below sea level now, but is not expected to rise; it is just a big saline lake. Ukraine does have a few important seaports, but again most of its territory and population are far away from the sea. On the second count, Russian agriculture can greatly expand northward and eastward, especially in the currently undersettled Siberian and northeastern European parts of the country. So can we assume that all is rosy? Not so fast.

Among the seemingly inevitable consequences of global warming will be an increase in midcontinental droughts, floods, and other extreme weather events (Lynas, 2008). Much of Russia's grain is grown today in the “black soil” zone of the steppe, where precipitation is already scarce. Compared to the United States and Canada, Russia irrigates far fewer hectares of its crops; it mostly relies on the summer rainfall and winter snowpack, both of which are expected to become spotty in the future. In fact, in the most recent assessment from the IPCC, the amount of precipitation over Ukraine is expected to drop by almost 50% by 2070. Extreme hot spells in the middle of the growing season in the summer may decimate sensitive summer crops, like corn and soy. The loss of snowpack in winter may affect the growth of winter wheat, which is the staple grain produced in the region. Southern Ukraine, the Caucasus, and Central Asia will be even more severely harmed. The treeline is predicted to shift upward by a few hundred meters, and alpine ecosystems may disappear in the Carpathians, in much of the Caucasus, and even in some Central Asian mountains. Melting of the permafrost in Siberia is likely to cause major structural damage to the existing infrastructure there (see Vignette 3.1).

Furthermore, although global climate change scenarios differ in regard to the exact scope and magnitude of change in climate parameters, all agree that the change is likely to accelerate as the nonlinear feedbacks in the climate system begin to kick in (see below for a Russian example). We also need to begin preparing for the unexpected. For instance, an abrupt halt of thermohaline circulation in the North Atlantic may temporarily shut down the Gulf Stream and make Western Europe colder than it is today very quickly. This may lead to a frantic political scramble among European nations for more fossil fuels from Russia, with some unpredictable consequences. Also, a catastrophic melting of even a small portion of the western Greenland ice sheet may abruptly raise the oceans by a whopping 4 m in less than 30 years, which would wipe out not only New York City, Los Angeles, London, and Copenhagen, but also St. Petersburg, Murmansk, Odessa, and Vladivostok.

One of the fundamental feedbacks that seem to be speeding up the global rate of climate change is occurring right in Russia. In 2005, a group of American and Russian researchers discovered, with surprise and alarm, that methane was being released from thawing eastern Siberian bogs at a rate five times as fast as was previously estimated from observations in Alaska. Each molecule of methane escaping into the atmosphere equals in its impact 20 molecules of carbon dioxide. When the new rate of escape is plugged into climate models, they show a higher rate of global warming than previously believed.

Although carbon dioxide is responsible for roughly 65% of the enhanced global greenhouse effect, methane is already contributing 20%. Thus Russia, with the biggest tundras in the world, will be contributing an increasingly great share of this gas to the atmosphere; this is ironic, since Russia only just joined the Kyoto Protocol process in 2004.