Should Siberia become independent

Claim: "Global warming will make Siberia the new breadbasket"

Proponents of the thesis that Siberia will become a granary in a warmer world often refer to a study by a research team from Russia and the USA (Tchebakova et al. 2011). Using several model calculations and scenarios, the scientists investigated possible climate developments for the Siberian region of Krasnoyarsk and the two south-bordering republics of Khakassia and Tuva up to around the year 2080. Most of the area is now too cold for the cultivation of arable crops such as wheat, oats and maize , Rice or sugar beet. According to the study, there has been significant warming since 1960. And this development will continue. This would be beneficial for agriculture, so the conclusion:

“By the end of the century, 50 to 85 percent of central Siberia will probably have become agriculturally usable ... In the course of global warming, the production of crops could double over the course of the century. Traditional crops such as grain, potatoes, silage corn could gradually migrate up to 500 kilometers north (around 50 to 70 kilometers per decade), and new crops (corn, apricots, grapes, pumpkins) could be introduced in the south of the area, depending on the future winter weather and the possibilities for artificial irrigation in the drier climate of 2080. Agriculture in central Siberia will probably benefit from global warming. "

In these - positive - results, however, two fundamentally important aspects are already hinted at, which coincide with the entire research on the topic: Firstly, in the course of climate change, the cultivation areas of traditional agricultural products will probably expand towards the poles due to temperature, i.e. afterwards in the northern hemisphere North. In return, however, it will usually get hotter towards the equator, precipitation will be less and more irregular - both of which will cause problems for agriculture there. Second, it is unclear how good the harvests will be in the newly reclaimed areas. The temperature is just one of many factors that determine the possible agricultural use of soils.

In addition to warming, other factors must also be considered - a very important one, for example, is the quality of the soil. The Siberia study by Tchebakowa et al. something important. But more on that later.

How does climate change affect agriculture?

The Fifth Assessment Report of the IPCC, which compiled the current status of global climate research in 2013/14, deals in detail with the consequences of global warming for agriculture. A whole chapter (Chapter 7 of Volume II) is devoted to this topic, as well as numerous passages in other chapters, such as those on climate impacts in Europe, Africa, Asia, Australia, North America and Central and South America.

The report describes in detail the multitude of effects that climate change can have on arable farming - and which must be taken into account in a reliable assessment of the climate impacts. For example, global warming is accompanied by a water shortage in many places, which is known to be a major problem for agriculture. There are also a number of physiological consequences for plants: a rise in temperatures usually leads to shorter ripening times. High temperatures during the flowering period can lead to reduced fruit sets. According to the IPCC, the knowledge gaps are still large in some cases. For example, much research has been done in the past on how crops behave at temperatures that are below their optimal development temperature, i.e. when it is too cool. But what exactly happens in fields when the temperatures are above the optimum for the respective plants is often still unclear.

On top of that. In addition to the direct effects of warming on plants, there are many other aspects to consider. Climate change will mean that extreme weather conditions will occur more frequently in a number of regions - and it is clear that droughts and heat waves, heavy downpours and hail showers have serious consequences for agriculture. The distribution areas of plant diseases or insect pests will also change. The harmful effects of ground-level ozone, which has also increased at the same time as climate change, are often overlooked.

On the other hand, global warming or its cause, i.e. the higher content of carbon dioxide in the atmosphere, also has a positive result: It stimulates photosynthesis, researchers speak of “CO2- Fertilizer effect ". This is stronger in some plants (so-called C3 plants such as wheat, rice, soy) than in others (so-called C4 plants such as corn, millet or sugar cane). In practice, however, this fertilizing effect is limited by a lack of water or extreme heat - phenomena that are expected in many places as a result of climate change.

The negative consequences already predominate today

The first effects of climate change on agriculture can already be felt today (see illustration 1). In Scotland, for example, global warming has contributed to higher yields in potato cultivation in recent decades (Gregory / Marshall 2012). In many other places, however, the consequences are negative. According to a much-cited study (Lobell et al. 2011), because of climate change since 1980, harvests of maize and wheat have been 3.8 and 5.5 percent lower than would have been expected without warming (for rice and soy So far, profits and losses have been roughly balanced globally). The conclusion of this study was:

“The climate trends [since 1980] have been strong enough in some countries to undo a significant part of the crop growth brought about by technological advances, CO2- Fertilizer effects and other factors have been achieved. "

In plain language: In the past, climate change has eaten up a significant part of the growth in harvests that could be achieved through technical progress, for example better irrigation. From this one can conclude that in the future - i.e. as global warming continues - even a stable supply (let alone improvements) will require permanent technical developments.

Illustration 1:IPCC overview of studies that examined the effects of climate change on average harvests, showing percentage changes in yields per decade (for example, a ten percent change over fifty years would be shown as a change of two percent). Losses have already been calculated for the past (bar on the far left) in the global overall balance, “n = 56” indicates the number of estimates recorded for this area (although individual studies may contain several estimates). The four bars on the right show projections for the future. Regardless of whether adaptation measures are taken (“with adaptation”) or not (“no adaptation”), crop losses are to be expected in the future, although there may of course always be slight crop growth (sections of the bars that rise above zero -Line protrude). However, even with adaptation measures, overall crop losses are expected in the future for both tropical regions (fourth bar from the right) and moderate latitudes (second bar from the right). The black line in the respective bar marks the mean value of all evaluated studies. The dashed line at the top of the graphic shows by which value (14 percent) the global harvests would actually have to increase per decade by 2050 according to calculations by the World Food Organization FAO in order to meet the increasing demand; Source: IPCC 2014, AR5, WG2, Chapter 7, Figure 7 (excerpt)

The consequences of increased ozone levels are even clearer. Without this man-made change in the atmosphere, the global yields for wheat and soy would be around ten percent higher today and for corn and rice around five percent higher (van Dingenen et al. 2009).

The effects of extreme weather are already particularly evident (although none of these events can be attributed exclusively to climate change. Overall, climate change brings more frequent and more severe extreme events): The record heat of summer 2003 in Western and Central Europe caused a decrease in grain production of around 20 percent (Ciais et al. 2005), and the 2010 heat wave in Russia caused the grain harvests to collapse by a quarter (Otto et al. 2012).

What consequences are to be expected for agriculture in the future?

In some areas, there is no question about it, agriculture will benefit from climate change - at least if it is not too severe. In addition to Siberia, the Fifth IPCC Assessment Report also names other regions in the far north, such as Scandinavia and Canada, and in the southern hemisphere, for example, Argentina, Uruguay and southern Brazil.

But what is the overall picture of future developments?

Firstly, this is characterized by a strong increase in global food demand, the main reasons being the continuing growth in the world population and increased consumption of meat (FAO 2012). Secondly, hunger and malnutrition are already prevalent in many parts of the world, especially in developing countries - or, in technical terms, “food insecurity”. Most of these countries are in the tropics. And even in these hot areas, climate change will lead to further warming. At the same time, the developing countries have the fewest resources to adapt themselves and their agriculture to a changing climate. Food insecurity is already greatest in southern Africa and in South Asia, notes the Fifth IPCC Assessment Report (Volume II, Chapter 7.1.2):

“The food supply in developing countries is heavily based on climate-dependent agriculture [for example, those without artificial irrigation]. These states are particularly vulnerable to climate change in connection with poverty and population growth. "

So one must by no means just look at the winning regions of climate change, but also look at the losing regions. According to studies, Africa and (South) Asia will be included (Lobell et al. 2008), which will be dealt with in more detail in the following paragraphs. Worldwide must be by 2050, according to a study in the medical journal The Lancet, due to the deteriorated food supply as a result of climate change, around 500,000 additional deaths are expected (Springmann et al. 2016).

Africa

Numerous studies have shown independently of one another that drastic crop losses are to be expected in Africa as a result of global warming. Schlenker / Lobell 2010, for example, put the losses in the regions south of the Sahara until the middle of the century for maize at 22 percent and for millet at 17 percent. Thornton et al. In 2011, when the mean temperature rises by around 4 degrees Celsius (this value is likely if greenhouse gas emissions continue to grow as before), average crop losses for beans of 47 percent and for maize of 19 percent are expected. In addition, climate change is likely to increase the annual fluctuations between the harvests (even with moderate average values ​​for yield losses, miserable individual years are to be expected); this makes it particularly difficult for farms to survive from one year to the next. This can have serious consequences for food safety.

Survey studies in which the results of such individual investigations were compiled show a high degree of agreement in the results. According to Roudier et al. In 2011, the mean value of the estimates for West Africa was crop losses of around eleven percent. Zinyengere, et al. In 2013, the analysis of 19 studies for southern Africa found an average value for maize cultivation, for example, of minus 18 percent by the middle of the century.

The conclusion of the IPCC is clear (Volume II, Chapter 22.3.4.1):

"Climate change is very likely [with more than 95 percent certainty] to have an overall negative effect on the harvests of the main food crops across Africa, although the differences in the extent of the yield losses are large."

Asia

The findings for Asia are somewhat less negative. There, too, research expects significant losses in many places. However, there are also more regions in Asia than in Africa where agriculture is likely to benefit from climate change. In Pakistan, for example, poor wheat harvests are expected in some areas and better wheat harvests in others (Hussain / Mudasser 2007); this depends primarily on the shift in rainfall and less on the temperatures. The picture is also mixed in China, where both positive and negative effects are expected even for the same region. In the North China lowlands, for example, the corn harvests could decrease by around 25 percent by 2080 (Tao et al. 2009), but at the same time the yields of winter wheat could increase by more than 80 percent (Tao / Zhang 2013). Winners and losers are also close to one another in Central Asia, as the Fifth IPCC Assessment Report explains (Volume II, Chapter 24.4.4.3):

“Some parts of the region could win (grain production in northern and eastern Kazakhstan could benefit from longer growing seasons, warmer winters and a slight increase in winter rainfall) while others could be losers (particularly western Turkmenistan and Uzbekistan, where frequent droughts negatively affect cotton growing influence the already extremely high demand for water for artificial irrigation and could exacerbate the already existing water crisis and man-made desert expansion). "

But precisely in areas in Asia that are very important for the production of staple foods such as rice, negative climate impacts for agriculture are to be expected (Wassmann et al. 2009) - this applies, for example, to the mega-deltas in Vietnam, Bangladesh and Myanmar (which are threatened by sea level rise) or the Ganges plain in northern India (which will be affected by the melting of the Himalayan glaciers). This study also identified a number of rice-growing areas in which even small increases in temperature can have serious consequences because they are already at the limit of tolerable heat stress - that is, the plants there are already confronted with critical temperatures, especially during sensitive growth phases. The IPCC warns that half of the wheat-growing areas in the Indian Ganges plain could also suffer from significant heat stress by 2050. Heat waves can cause severe crop losses, especially during the flowering period of arable crops (Deryng et al. 2014, Teixeira et al. 2013).

Researchers cite South Asia as a future focal point because the region is considered to be just as vulnerable to climate change as Africa and where many people live who are already suffering from food insecurity (Schlenker et al. 2008). An overview study for South Asia, which evaluated 114 different model calculations by different research teams, found a mean value of expected crop losses by 2050 of 16 percent for maize and eleven percent for sorghum, while gains and losses roughly balanced each other out for rice (Knox et al. 2012 ).

Why doesn't agriculture adapt to the changed climate?

Adaptation measures can mitigate the consequences of climate change in all areas of the economy and life, including agriculture. For example, cultivation methods and sowing times can be changed. One of the most important measures is to switch to or develop plant varieties that are better adapted to changing climatic conditions. But when the temperature rises there are limits up to which it is even possible for plants to adapt. And against the frequent occurrence of extreme weather events such as storms, droughts or floods, adaptation measures by farmers are only of limited help in any case.

The IPCC writes in its Fifth Assessment Report on this subject (Volume II, Chapter 7, Executive Summary):

“On average, adapted agriculture improves the serious by an amount that corresponds to around 15 to 18 percent of today's harvests. However, the effect is highly variable - the range extends from possibly negative to negligible to very substantially positive. The expected benefits of adaptation measures are greater in temperate latitudes than in the tropics. "

Up to an increase of around two degrees Celsius (this does not mean the mean temperature of the earth, but the respective local temperature!) The IPCC sees good opportunities for agriculture to adapt.However, especially in the poorest regions of the world, where adaptation measures will be most necessary, both governments and individual farmers lack the resources for this (Hertel / Lobell 2008).

With local temperature rises of four degrees Celsius, however, adaptation measures could hardly compensate for the harvest losses in many places. The IPCC therefore calls such warming rates "very significant risks and challenges for food security". However, such temperature rises will increasingly occur in the coming decades - because four degrees Celsius local warming can already be achieved if the global warming average is still well below it.

The further the century advances, the more negative the outlook for the IPCC will be (Volume II, Chapter 7.4.1):

"By the 2030s it is likely [i.e. in the terminology of the IPCC: 66 to 100 percent certain] that there will be crop losses [in the global overall view]. By the 2050s, it becomes as likely as not [i.e. 33 to 66 percent certain] that the losses are more than five percent. From the 2080s onwards, it is very likely [i.e. 90 to 100 percent certain] that crop losses will be recorded in the tropics - regardless of adaptation measures. "

Figure 2:IPCC overview of studies in which the consequences of climate change on harvests in numerous regions (tropical and temperate), for various emission scenarios and in the event of successful or non-implemented adaptation measures were examined. The expected changes in income for the coming twenty-year periods are shown. For the period 2010 to 2029 (bar on the far left), projected harvest increases (blue tones) and harvest losses (orange tones) are almost balanced. At the end of the century (bar on the far right), the picture polarized with advancing climate change. Slight changes (light color tones) have now disappeared, some studies for certain areas still show crop growth (blue tones), but the vast majority of the individual studies anticipate - sometimes dramatic - yield losses (orange tones). Relatively few estimates were available for warming scenarios of four degrees Celsius or more; Source: IPCC 2014, AR5, WG2, Chap. 7, Fig. 5

And how much do the winners of climate change really benefit?

Finally, a closer look at those regions in which global warming will lead to better harvests in the foreseeable future. Such areas can also be found in Europe, although the continent's overall balance is mixed. While harvest losses of up to 25 percent by 2080 are expected for southern Europe as a result of increasing drought, the losses in western and central Europe are likely to be lower (Ciscar et al. 2011) and even positive effects can be felt in Scandinavia (Bindi / Olesen 2010). For example, researchers speculate that the cultivation of silage maize, which is unthinkable there today, could become possible in Finland by the end of the century (Peltonen-Sainio et al. 2009).

But what a warming in the far north and an expansion of arable land will really mean for crop yields is difficult to calculate. Because the temperature is - as already described above - only one factor for plant growth. Studies in Finland, for example, have shown that the warming that has already occurred did not lead to an improvement, but on the contrary even to a deterioration in the harvests - because it also became drier at the same time (Peltonen-Sainio et al. 2010). In addition, rising temperatures are likely to cause previously unknown plant diseases and insect pests to spread (Hakala et al. 2011).

The IPCC therefore warns against hasty and exaggerated expectations in the climatically favored areas. In practice, higher harvests would only occur if "suitable plant varieties are available and the soil quality and other conditions are suitable" (Volume II, Chapter 7.5.1.1.1):

"This may especially happen in Russia, Canada and the Scandinavian countries, although the potential may be lower than previous analyzes showed - the reasons are increasing weather extremes, water scarcity and various institutional barriers. In many of these cases, expansions to the north should only compensate for this which is being lost due to the reduction in cultivation areas in the south, less rainfall and higher temperatures. "

For precisely these reasons, the bottom line is that the expansion of arable farming to Siberia will probably not even bring benefits in Russia, let alone on a world scale. A closer look reveals that the areas in the far north that can be newly developed as a result of global warming have a rather poor soil quality (Kiselev et al. 2013). The study by Tchebakova et al. expressly points out that the soil quality will be the “limiting factor” in the increase in arable land in Siberia. In return, however, as a result of climate change, increasing drought is expected for regions between the Black and Caspian Seas, the previous “breadbasket” of Russia (Dronin / Kirilenko 2008).

"For the 21st century, our own study, like others, shows that the risk of severe droughts is increasing in the zone with the most fertile soils. In today's climate, they are only common in a relatively small area in the Lower Volga Basin. In the future, will the area of ​​frequent, severe droughts is likely to extend to a considerable part of the south of the European part of Russia ",

warn Dronin / Kirilenko 2011). In the summary of their study, they state that there may be the view that global warming is beneficial for Russian agriculture. Her cool conclusion, however, is that it is "unlikely that this view will hold".

klimafakten.de/Stand: July 2014;
last updated: March 2016