A glacier in my field

In a world that is becoming more and more fast-paced and in which demands are constantly increasing, it is difficult to pause for a moment, take a step back from what you are doing and take a look at the big picture.

The whole attention often is focussed on the plant protection agent issue. This applies to the public with regard to the environment, but also to ourselves with regard to economy and technology. The common thinking is that plant protection is the most important yield factor for cereals or row crops like maize. However, we all – the agrochemical industry and the farmers – know: the climate and its vagaries, lack of water (or the opposite!), hail etc. are the most limiting factors.

A study carried out by Biochem & Mol Biol Plants, Buchanan, Gruissem, Jones and the American Society of Plant Physiologists with regard to the influence of different stress factors on the yield of maize, wheat, soybeans, sorghum, barley and oats confirmed this observation: abiotic stress factors have significantly more influence than their biotic equivalents. Abiotic stress factors are any factors that inhibit growth because of extreme situations, e.g. drought, too much water, particularly low or high temperatures. Biotic stress factors are all attacks caused by living organisms, e.g. fungi, bacteria, insects or weeds. In the US, the negative effect of fungi and weeds on the yield of all above mentioned crops amounts to 5 to 10%. For the stress factor climate change, this percentage ranges between 66 and 82%.But what is done in the research sector to stabilise yields in the face of the climate change and especially of water shortages?
The glaciologist Heidi Sevestre was the keynote speaker at a conference about climate change that was organised by the AGtech company Elicit Plant in France. She quite specifically linked the consequences of the deglaciation to the climate change and the use of arable land. In an entertaining and quite humurous way, she made her literally icy point. terraHORSCH summarises her speech.

From a country named Svalbard

Heidi Sevestre lives in the Arctic. In a region where, inevitably, no crops are grown: in Spitsbergen. “It is an archipelago that is dominated by ice. The soil is permanently frozen. It is a paradise for glaciologists. More polar bears live there than people and it is located right at the pack ice. We live in Longyearbyen, the epicentre of the climate change. Did you know that statistically Europe heats up faster than the rest of the world? In Svalbard, the Norwegian name of the archipelago, heating proceeds five to six times faster than the global average. In the past 50 years, the temperatures there increased by 3° to 5 °C. This is why we have the impression to live in the future. Every day, we see the consequences of this warming: meltwater, avalanches, rain in winter. But what is the reason for this rapid melting? The larger and older an ice floe is, the whiter it is and the more it reflects the sunrays – this is how the planet is cooled. So we need these white areas. But in the past years, we destroyed them. Some months ago, a study was published: by 2030, we might experience summers without ice. Little by little, we are passing the climatic tipping point.”

The importance of the glaciers

The scientist continues: “So what is the link between the glacier world and agriculture? The common thread that unites all of us in this room is water. Without water, we won’t get far. Water is currently bearing the brunt of the climate change. Imagine our water reserves, our rivers, the main arteries of our country. Water is life. It is what drives our activities every day. We have become used to always having water, rain and subterranean water reserves. But this is changing. The most striking aspect is the decrease of the glaciers, e.g. the Trient glacier in the Swiss Alps. This is the best climate barometer. You can, of course, measure the CO₂ increase but you cannot see it. However, if a glacier disappears, you can see it. And with the glaciers that disappear, the natural drinking water reserves will disappear, too. But where does the water in Europe come from? Mainly from the mountains. We need water: for drinking, to generate energy, to cool nucleaer power plants, for tourism and for agriculture. However, every ton of CO₂ that is released in to the atomosphere makes our water and snow reserves melt. There is no doubt that we will lose the glaciers of the Pyrenees. By the end of the century, the glaciers of the Alps will disappear, too.”

Influence of the winds

“How the winds on earth between Europe and the Arctic develop partly depends on the fact that the Arctic is frozen. If this is the case, we can see a stable polar vortex. In short: The colder the Arctic is, the faster turn the winds. This is how the seaons develop“, Heidi Sevestre explains. The so-called jet stream that consists of polar and subtropical currents makes the weather phenomena in Europe move evenly from west to east. Low pressure areas stand for rainy and windy weather whereas high pressure areas bring clear weather conditions. The jet stream is responsible for the cycle of high and low pressure areas that make up our seasons.

However, the temperature difference between the Arctic and Europe becomes smaller and smaller. “The smaller the temperature difference is, the slower are the winds. And like a river that is flowing slower and slower, the winds start to form meanders. There can be air masses that flow from south to north as it is the case in hot and dry periods. Or air masses that come from the Arctic and cause early or late frost. And these conditions can be blocked for days, even weeks.” Thus a high pressure area can remain at the same location for quite a long time. Depending on where it is, a high pressure area can either bring heat or drought periods or heavy rainfall – for several weeks. “Go regularly to windy.com. It shows the development of the winds on earth. This jet stream the meanders of which become more and more distinct shows how the weather changes completely.” The seasons as we have known them so far are constantly changing. A completely new reference system is being created.
But beware: Heidi Sevestre points out that the climate change differs all over the world. The wavelike jet stream runs through the whole world. Some regions are more prone to cold periods whereas in other regions it is getting hotter. These new wind currents cause chaos. But the areas that are most affected by the climate change are not always the weakest. With regard to food safety, the cards will be re-shuffled in the long term as the 2023 IPCC studies clearly show.

Less water … more water?

“The melting of the ice combined with a temperature increase of the oceans results in a rise of the sea level This is nothing new. The sea level currently increases by 3 to 4 mm per year. But this figure could rise even more with the melting of the ice in Greenland and in the Arctic, the largest continental ice reserves of the earth.” At the moment, Greenland loses more ice in summer than is created in winter – the mass balance thus is negative. “As a result, the sea level rises. If the ice in Greenland melts completely, the sea level all over the world will rise sooner or later by 6 to 7 m. And if the ice of the Arctic, too, disappears completely, it might even be 58 m. At best, we will have 50 cm more water at the end of the century. But we have to be aware of the fact that this might happen much faster.”
Of course, this rise has a consequence on the ocean current that also determines the climate. To make sure that the current functions properly, temperature differences in the water and also differences with regard to the salt content and the density are necessary. The water in the polar regions heat up faster than elsewhere. And ice makes the water soft. You can also notice a slowing down of the currents in these oceanic waters. As a result, the climate as we know it will largely be turned upside down.

Who or what releases CO₂?

“The climate warming is changing the permanently frozen soil, the permafrost.” We must not forget that 25% of the northern hemisphere consists of these soils. If they melt, they release a large amount of CO₂, but also methane that can warm up the climate 80 times more than CO₂. ”Today it seems that the melting of the permafrost can release as much greenhouse gas as the whole of Japan. By 2100, it might be as much as India, Europe, even the US, depending on the additional degrees of temperature that are reached. We will have to cope with the emissions of the permafrost. Another related phenomenon? New land could become available.“

Significant impact on agriculture

According to a report of the IPCC, a committee established by the United Nations, from 2020, 59% of additonal arable land will theoretically be available between 2060 and 2080. In this respect, it seems that Russia is particularly favoured. Especially with regard to the wheat production in Sibiria. The same might be true for Canada where there also are a lot of permafrost soils that will melt. “But all these areas are carbon sinks. And we have to keep them intact to limit global warming and, thus, maintain a sufficient level of food safety.”
Of course, the climate warming will empower the farmers of the northern hemisphere. But the international average of the yields will decrease while the world population continues to grow. The immigration flows will increase because of this shifting of the arable land and the yield potentials. This is why we urgently have to limit the warming and thus the impact of agriculture on these newly available land. Apart from the fact that we concentrate on the macro aspect it is obvious that the climate warming that disturbs the seasons complicates the vegetative development cycles of the traditional crops. We will perhaps, but this is not sure, have the same annual amount of rainfall – but with extreme weather phenomena over long periods of time: frost, drought, floods.
As we already mentioned at the beginning of the article, it is worth remembering that the majority of the current expenses for research and development in agriculture is spent on herbicides and fungicides even though the climate change affects yields by 66 to 82%.
But what else can be done in the research sector to maintain yields in the face of climatic changes, especially water shortages?

Is it already too late?

“What can we do? We have to fight for every fraction of a °C. The measures we take today will bring advantages well before 30 years have passed. If we slacken the reins and reach +3 °C, we can be pretty sure that some thresholds will be exceeded marking a point of no return for the ecosystems. The latest scientific studies for example seem to show that in case of a temperature rise of more than 2 °C an irreversible destabilisation might start in Greenland. The same applies to the Western Antarctic, a majority of the tropical coral reefs, the permafrost soil of the northern hemisphere, the ice of the Barents Sea and a majority of our mountain glaciers. The disappearance of these ecosystems might affect the climate change even further. But we have to fight for every tree, every meadow, every carbon sink. Every tenth of a degree that is not added is a benefit for EVERYTHING, water and food safety. We have to decarbonise. Governments and companies are taking action. We can be sure of that. The article about agrovoltaics in the last issue of terraHORSCH is an excellent example. Wir have to continue along this path. “Agriculture is one part of the problem – like we all are. But agriculture also is a solution!” Heidi Sevestre points out.