How to effectively heal the climate? - An example of the recovery plan for the Košice region of Slovakia

By Michal Kravčík1)

A lot has been said about climate change. The scientific community perceives climate change as a consequence of human anthropogenic activity by increasing the concentration of CO2 greenhouse gases. Let’s compare the graph of average temperature growth since 1960 with the growth chart of atmospheric CO2 for the same period (Figure 1). We can see they are nearly identical, and there should be no doubt about the direct correlation of CO2 on the temperature regime of the country. Therefore, most scientists working on climate change models do not doubt anything else could cause climate change.

Are we asking the right questions?

Suppose we focus on the physical processes of the temperature regime of the planet Earth. In that case, we need to consider all impacts on climate change and examine water as the most abundant greenhouse gas.

There are at least two laws of physics that offer a different explanation for the anthropogenic impact of humankind on climate. The law of conservation of energy and the second law of thermodynamics look beyond CO2 as the primary driver of climate change and offer answers.

Figure 2 explains how solar radiation transforms when it hits the Earth’s surface. Provided there is enough water in the ecosystems, a significant part of the Sun’s radiation is absorbed through evaporation and the ongoing transpiration of water through the vegetation during intensive photosynthesis. Up to 70-80 percent! The remaining solar radiation will contribute to soil heating (5-10 percent), reflection (5-10 percent), and warming of the troposphere (5-10 percent). It is worth noting that the evaporation of one cubic meter of water consumes 700 kWh of energy from the Sun. According to the law of conservation of energy, solar radiation is transformed into latent heat, which is carried by the evaporated water to the colder layers of the atmosphere. The evaporated water condenses in colder layers and forms clouds. At the dew point, rain forms, and latent energy is released into the atmosphere and warms it per the energy conservation law mentioned earlier.

Suppose we damage the existing lush ecosystems, drain and cause the landscape to dry up, or cover and seal it with impervious surfaces. In that case, we disallow the rainwater to permeate into the soil, and the natural evaporation will decline. In other words, the Sun’s energy absorption will decrease when the water evaporation decreases. In such circumstances, less water evaporates, and fewer clouds form, causing more sunlight to reach the Earth’s surface. With the decrease of natural evaporation from the degraded area, the production of sensible heat, which accumulates in the troposphere, increases, and the environment overheats and creates a thermal island (heat dome).

It’s a unique biotic pump that has been drawing the heat from the troposphere for thousands of years, like a car engine radiator. It works unless the radiator breaks down. Let me explain. What happens if the existing balanced ecosystem holding an abundance of water gets damaged and dries up? What happens when a degraded ecosystem offers no water to evaporate from the landscape? If we dehydrate “ a balanced ecosystem”, the sunlight absorption on the water vapour can drop to zero. What happens to the incoming solar energy, then? The water vapour cannot result from evaporation and plant transpiration and is absent in such a case. If solar energy is not transformed into water vapour, it is transformed into sensible heat, overheating the troposphere, and generating heat islands (heat domes).

The left side of Figure 2 tells of a landscape in which we have made holes through and drained water from an ecosystem. (Like when a car radiator gets pierced). Therefore, less water evaporates from the Earth, less energy gets transported to the colder layers of the atmosphere, and even fewer clouds form in the sky.

As a result, more sunlight reaches the Earth’s surface. It transforms into more sensible heat that accumulates in the troposphere over those arid parts of the Earth. In this way, heat islands (heat domes) are formed, overheating the landscape, especially in cities, and in poorly managed and drained agricultural land.

For a better understanding, I offer a heat distribution scheme in two environments.

(Figure 3). There are more clouds in the sky in an environment where there is plenty of water (left part of the picture) because more water evaporates from the ground. Through the clouds, less sunlight enters the troposphere. At the same time, less sensible heat and more latent heat are produced from the incoming sunlight on the Earth’s surface as more water evaporates from the soil.

The right side of the picture talks about dry land. Less water evaporates from the ground, less energy is transported to the colder layers of the atmosphere, and even fewer clouds form in the sky. As a result, more sunlight reaches the Earth’s surface. It transforms into more sensible heat that accumulates in the troposphere over those drier parts of the Earth.

During the condensation of evaporated water vapour in the atmosphere, clouds form, which reduces the permeability of solar energy through the clouds and alleviates the overheating of the atmosphere below them.

The solar radiation that does not get reflected but penetrates the clouds is absorbed by the vapour (blue arrow) when it hits the Earth’s surface. The solar energy that is not consumed by the vapour is converted into heat (red arrow) and heats the above-ground atmosphere (troposphere).

In a landscape with enough water, solar energy transformation by the vapour is dominant (blue arrow), as liquid water molecules are available to consume the incoming solar radiation and change the state from liquid to gas. In a landscape where soil moisture is low, the unabsorbed heat transforms into sensible heat. It overheats the ground layers of the atmosphere (red arrow).

According to the second law of thermodynamics, the converted solar energy is transported by the evaporated water to the colder layers of the atmosphere and heats them. This reduces the temperature gradient between the ground and upper layers of the atmosphere, preventing the growth of weather extremes.

Let’s look at a city like Budapest, Hungary. Before the people of Budapest developed its land with buildings and roads, the rainwater would evaporate, and saturate the ground, supplying the vegetation and groundwater aquifers. These days, at least 100 million cubic meters of rainwater collects annually in the regulated drainage infrastructure and empties to the Danube River. In the past, this water would evaporate into the colder layers of the atmosphere. Instead, more than 70 TWh of sensible heat per year is now released from this territory into the troposphere. Therefore, summer temperatures have been 3-5 degrees Celsius lower in the past. Interestingly enough, the Hungarian economy utilises 70 TWh in 1.5 years (Hungary’s total energy consumption in 2018 reached almost 40 TWh).

On this principle, we have developed a Green Restoration Plan for the Košice Region of Slovakia, which was approved by the Košice Regional Parliament on 19 February 2021. It is an integrated landscape and watershed programme that will benefit several, providing a roadmap for ecosystem restoration. The Plan’s implementation will increase the water retention capacity of the damaged landscape of the Košice Region by 60 million cubic meters with a total cost of 400 million €.

This Plan will contribute to creating 3200 jobs and the annual sequestration of 6.6 million tons of CO2 to vegetation and soil, a yearly increase in the fertility of the agricultural landscape by €30 million, the restoration of dried water springs of 12,000 liters per second, an increase in latent heat production and the return of more regular rainfall, the formation of horizontal precipitation (dew), a decrease in the production of sensitive heat and the mitigation of atmospheric disturbances with a reduction in the incidence of weather extremes and flood risks, as well as an average temperature drop of 0.77 degrees Celsius. The projected return on investment in this programme is well below ten years. Such a model can be implemented in all parts of the world, increasing climate, environmental, water, and social security.

Michal Kravčík, of People and Water International, Slovakia, is a hydrologist and environmentalist. He was awarded the Goldman Environmental Prize in 1999, for his contributions to the water management of the Torysa River.