12 Aug 2021

Atmospheric Physics Institute Deputy Director Vladimir Semyonov: the climate is always changing but not as rapidly as now

Vladimir Semyonov

Vladimir Semyonov
Courtesy photo

Atmospheric Physics Institute Deputy Director Vladimir Semyonov has given an interview to Interfax in which he speaks about the pace of climate change and weather abnormalities both in Russia and Western Europe.

Question: We are witnessing natural paradoxes more frequently than ever, with one part of the Earth, even one continent experiencing heat and drought, which brings about forest fires, while, nearby, rivers overflow, bringing about flooding, some of it disastrous. Is this related to the rapidly changing climate or human activity? Why are these changes not global but occurring only in certain places?

Answer: Naturally, climate change is a global problem. It is a scientific, philosophical and purely human problem.

Let's have a look at history. In the late 19th century many people were shocked by first experiments to cause artificial precipitation by firing shells at clouds. Sometimes that coincided with rains, causing much commotion. There was a lot of debate, religious and philosophical, as to whether humans are entitled to do such things, whether this doesn't go against God. Previously, this was a prerogative of higher powers.

But that ended. Now, unlike those experiments conducted a century ago that were to no avail, we have developed effective means of causing precipitation, and we actively use artificial rain, for example during parades. Now we are to a certain extent psychologically undergoing things similar to the one at the end of the 19th century. For the first time in Earth’s 4.5 billion years, humans are capable of changing the climate by results of their activity – and on a global scale! This has become obvious not only to generations but also to young people who have been alive for, say, 30 years. The climate is changing before their own eyes, and as a result the weather is changing, including in Russia. The temperature has risen almost two degrees over the past 50 years. This is causing visible changes. Moreover, we, the climatologists, can see this on our devices. Meteorological satellites have continuously been measuring temperature on almost all planet's surface for about 40 years, which gives an opportunity to get an absolutely complete picture of climatic changes.

Satellite data prove that the temperature has been growing strongly as a result of carbon emissions. Not only greenhouse gases but also solar radiation coming to the Earth and heat radiation leaving the Earth is well tracked. So, we are not only measuring the growing concentration of greenhouse gases in the atmosphere but also their impact – especially over the past 20-30 years – on the changing balance of the planet's warmth, and circumstantial evidence gives a good understanding of these changes over the past 50 years at least. These data correlate with the warming witnessed and assessments made back in 1970s.

Naturally, if the planet's population was hundreds of thousands or a million people, then climatic changes wouldn't have been that rapid. They would have been caused by other factors, changes in the parameters of the Earth orbit, solar activity, tectonic movement – and tectonic plates move 5 to 10 centimeters a year – and the composition of the atmosphere, rather than human activity. The configuration of continents and oceans has been changing along with climate change. And even earlier climates depended on processes in the Earth's mantle and other natural factors.

Q.: The climate has always been changing but the pace has been growing more rapidly. Is this the case?

A.: Of course. The Earth’s population has been growing all the time and has eventually reached the level that is now a factor of climate change. Almost 8 billion people now live on the Earth, mainly in cities with intense infrastructure. Their activity has resulted in greenhouse gases that, as we have already noted, influence the composition of the atmosphere, which means the climate on the planet. It is quite easy to understand that the issue of the need to reduce activities harmful for the atmosphere has arisen at the highest political level over the past few decades.

Q.: It is common knowledge that by their own development humans cause damage to the nature and thus to their health. However, I read recently in an academic journal that climatologists studying the Arctic Ocean, as they say, reached the shore and together with permafrost researchers came to a conclusion that changes somewhat the thesis that humans are doing the utmost harm to the atmosphere. They established that carbon emissions in Arctic permafrost areas are much higher than industrial carbon emissions. Does this mean that nature itself adds to, if not exceeds, the harmful impact on the atmosphere? Is there any point then in crossing swords in the fight for reducing harmful industrial facilities?

A.: First of all this is wrong. We can see the changes in concentration, we know the balance, how much humans emit, and we assess approximately how much the Ocean and terrestrial ecosystem can absorb. This is all at the level of hypotheses, according to which methane hydrates emit methane flows when permafrost is melting on the shelf. Let me say once again, these are just hypotheses. Analyzing satellite data of methane and carbon measurements, we can see any tendencies for these values to change over the past 15-20 years. They don't record any additional growth in the high latitudes of the Northern hemisphere.

Q.: Then how can this data be explained?

A.: Very simple. Experts sail in vessels over a certain section, and they record higher methane levels. They think that these data prove that permafrost started to emit methane which affects climate change. But this is local data, and other studies show that the methane concentration in this district changes because of crust fractures, as methane hydrates start to melt where temperature is higher. This has nothing to do with global warming, these are local processes and they have no considerable influence on the global balance. This is just speculation and hypotheses that are substantiated by nothing but local experimental data.

Q.: What is the explanation for simultaneous but absolutely different weather - in one part of a country or a continent there are extremely high temperatures causing drought and fires and in another there are disastrous floods?

A.: As for simultaneous floods and heat waves, these are in general interrelated processes. Heat waves in the European part of Russia are linked to a blocking anticyclone. Here in middle latitudes air masses are moving from the west to the east. This feature is linked to the circulation of the atmosphere due to the south-north difference of temperatures. And if an anticyclone develops, it doesn't allow this flow to go. But in summer humid and chilly air masses come here from the Atlantic. The continent is warming faster and more strongly under the summer sun, while the ocean is inertial and its temperature roughly remains at 18-20 degrees. When an anticyclone develops, it blocks chilly oceanic air masses bringing heat here. In addition, an anticyclone means clear skies and solar radiation reaches the Earth surface, warming it up.

This is one side of the coin. The other deals with Europe. Cyclones that previously came from Europe to our territory and then move further now get stuck in a jam. That humidity stays in one place, and instead of one day of pouring rain, it can precipitate in the same place for several days.

Q.: Does this mean that heat in European Russian cause rains in Western Europe?

A.: Almost. Our south is also linked to the 'games' of cyclones and anticyclones. In particular, more humid and warmer air masses over the Black Sea, which got 2.5 degrees warmer in the past 40 years, cause heavier rains than before when a cyclone passes along the shoreline.

Q.: Can humans somehow influence this?

A.: Humans cannot influence the formation of cyclones and anticyclones. Colossal energy is needed for this. According to some estimates, the energy of one cyclone, not the biggest one, is equal to the energy that the humankind generates instantaneously. This is enormous energy and it is absolutely impossible to influence the formation and the dynamics of such processes.

Q.: Is it possible to foresee floods and droughts?

A.: This is a good and important question. Our institute is intensively addressing the predictability of such phenomena from one week to a month. The thing is that a regular weather forecast can be trustworthy for three to five days, one week at most, and beyond this period weather is accidental. Now, forecasting methods for longer period are being developed, but this is a new, a different science. We are trying to move ahead in this respect. And we are not the only ones. In particular, the European forecasting center has been intensively studying this topic for the past 10 years. They published an article recently saying that they were able to forecast the 2010 heat wave approximately one month before it reached Moscow.

But we have to understand that we all pretend to be smart after the act. That is why this is just a new important area that is developing intensively. But honestly, there is no considerable success so far. Other methods which we want to develop should be used.

Nevertheless I would say that there was a forecast about Germany before the flooding. Meteorologists forecast the intensity of precipitation and its location. So, the amount of precipitation was known quite accurately a day before. This is enough time to take urgent measures. But this didn't happen. Having been aware of the upcoming events, nobody took serious measures. This is strange. It is also possible to work in this area, to develop a more serious attitude to forecasts and the risks of such phenomena.

Q.: We've been talking about floods. And what about fires?

A.: I would say the same about heat. We cannot forecast when a blocking anticyclone comes. It came suddenly, we recorded that. But we don't know when it will collapse. We can tell by the nature of circulation that, yes, this blocking anticyclone is likely to last for at a week. But further on other processes come into play. It can self-sustained, it can stay in one place for, say, two or three weeks, or even a month, and in such conditions the risk of fires naturally grows. Again, preceding conditions need to be taken into consideration here. For example, if soil is humid, this is good, because moist soil, as it evaporates humidity, doesn't allow the surface to warm up. If soil is initially dry, then a week or ten days are enough for soil to warm up and drought to develop.

In such conditions we get fires, turf and forest ones, causing the most negative consequences as in 2010 - heavy atmospheric pollution, fires and so on. But again as with floods measures need to be taken to prevent the consequences of such heat waves. Much was said about this. In 2010, turf areas of the Moscow region were previously meliorated, there were canals to deliver water there to make them humid. Everything fell into neglect. The same applies to forests, clearings, the chopping of old dry trees, and their removal, this should all be addressed actively. This is a comprehensive problem and it is linked not only to the climate but also to actions of humans on the planet's surface, to how they are preparing forests and infrastructure for such events.

Q.: We are reaping the fruits of our carelessness and indifference to nature.

A.: Yes, indeed. But there are other things as well. We are reaping the fruits of our let me put it this way, greediness and desire to make big profits.

Q.: What should we expect in the next 10 years?

A.: Warming will continue in the next 10 years. The pace will roughly be the same as in the past 20 years. So, the temperature in Russia grew about 1.2-1.5 degrees in the past 30 years. In general, this is a lot. About 0.4-0.5 degrees of warming should be added over a decade. The climate will roughly be the same as it is now but noticeably warmer than at the end of the 20th century. Warming can be expected to continue until the middle of the century. That is why some adaptation measures need to be taken right now.

I always say that climate change is not deadly for humans. They will survive even a stronger warming and stronger cooling. The problem is the costs to the economy, human life and health if we don’t prepare for the changes!