home of the Ozone
The layers of our atmosphere from sea level to outer space: troposphere (mountain peaks, airplanes), stratosphere (ozone, meteorological balloons, Armrstrong – line), mesosphere (meteors), thermosphere (aurora lights, space plane, Karman – line), exosphere (particles flying out into space). There is no sharp line between the different layers; they are constantly mixing, migrating a little lower, a little higher.
STRATOSPHERE
18 – 50 km
By the way, it begins at an altitude of 8 km at the polar circles, because the soil temperature is the lowest here. And the stratosphere “begins” where the heat coming from above and the warm air flow coming from the troposphere create a kind of balance.
This is where the medium became suitable for the formation of the ozone layer. The ozone layer prevents the further penetration of harmful rays, thereby protecting life on earth. However. Since the air is not exchanged here, all emitted harmful substances are trapped here for a long time, damaging the ozone layer (it provides inadequate conditions for its healthy preservation; ozone holes).This process has an impact on our Earth’s climate changes. By the way, the stratosphere is shrinking and thinning continuously due to harmful substances. This is also what the Paris Agreement is about.
This is where the meteorological balloons fly and the temperature rises again in this layer. And here is the so-called Armstrong – line at a height of 18-19 km. But what do we need to know about it?
Tropopause and Stratopause
The tropopause is the lower limit of the stratosphere, where it is about -42 °C. Transition between the troposphere and the stratosphere. From there, the temperature rises again to the upper limit of the stratosphere to the stratopause, where the temperature is around 0 °C and the atmospheric pressure is one thousandth of that above sea level. Above this layer, only 0.1% of the total mass of our atmosphere is found.
Ozone layer
It was formed about 500 million years ago. The ozone layer was discovered in 1913 by Charles Fabry (June 11, 1867 – December 11, 1945) and Henri Buisson (July 15, 1873 – January 6, 1944) French physicists. It was later investigated by G. M. B. Dobson (February 25, 1889 – March 10, 1976) British meteorologist, who developed a spectrophotometer (Dobsonmeter). With this, it was possible to measure the ozone concentration in the stratosphere from the earth’s surface. Between 1928 and 1958, he established a worldwide network of ozone monitoring stations, some of which are still in use today.
By the way, the scent of rain can be linked to ozone.
Rain actually has no scent. What we feel is a substance called geosmin released by a bacteria. Among other things. The smell of rain: petrichor (greek). Petra means rock, ichor is the liquid in the veins of the gods. Geosmin is produced by the death of a certain type of bacteria living in the soil. This substance is also found in beets, radishes, and corn, for example. The other is an oil released by plants in dry weather to prevent germination (how beautiful nature is). And, the rain also brings something with it: the smell of ozone. It’s a bit complicated how they mix, but when it starts to rain, we can smell the ozone.
But, back to the overall phenomenon. When rain falls to the ground, it “frees” these substances, and the mixture of these substances is referred to as the scent of the rain.
Ozone in the Stratosphere
The stratosphere has layers of different temperatures, which is due to the ultraviolet radiation emitted by the Sun from above. As a result of the ultraviolet radiation, some of the oxygen molecules are broken up and new ones (3-atomic ones – O3) are formed. The ozone molecule (O3) is an unstable molecule consisting of 3 oxygen atoms. They make up the ozone layer. Ozone absorbs and converts harmful ultraviolet rays into energy, which increases the temperature of the layers while being destroyed. Surely, what creates it, it also destroys it. It’s an eternal cycle, broadly speaking.
90% of the ozone in the air is found here in the stratosphere. Nearly 3 million tons, but this is still only 0.00006% of the mass of the atmosphere. Average thickness is 2 – 5 mm.
The above-mentioned layers of different temperatures do not mix with each other, they are stable, as a result of which the harmful substances introduced stay there for a very long time, thus influencing the climate of our Earth and the thickness of the ozone layer. For example, during a major volcanic eruption, the materials and particles that enter here will remain here for at least 2 years.
Here, only horizontal flows occur, which means that whatever entered this sphere at a given point, it’s circulates around the entire Earth, is not pushed outwards or inwards, and does not stay in one place at the given entry point.
Ozone in the troposphere
Ozone also has a harmful effect, especially near the ground. It blocks the reradiation of heat, acts as a greenhouse gas, and can lead to the development of respiratory diseases. It is a component of smog.
But, how do particles get into the stratosphere?
There is no weather, clouds, wind in here. Specifically, polar stratospheric clouds can form. All the substances we emit can and do stick to the clouds. Such as: chlorine, bromine compounds, halogenated hydrocarbons.
Polar stratospheric clouds are formed when the temperature exceeds – 78 °C in the polar circles and in the northern regions, at an altitude of 15 – 18 km. This can happen from the spring of every year, for an average of 4 months, when higher temperatures prevail in the arctic circles. Since there is no air flow between the troposphere and the stratosphere, i.e. the exchange of particles is almost zero, there is therefore hardly any water vapour in the stratosphere. Thus, clouds only form when it is so cold that the small amount of water present condenses and forms ice crystals. These ice crystal clouds do not cause precipitation.
These beautiful, rainbow-colored, pearlescent clouds have a particularly harmful effect on the integrity of the ozone layer.
We can divide them into two categories. Pearlescent light actually belongs to category II clouds, and they mostly consist of water ice. Type I are divided into subcategories according to their chemical composition. The content of these clouds is: water, sulphuric acid, nitric acid, chlorine, for example.
The particles that reach the stratosphere are long-lived and very stable, which is why they can reach this far. Ozone is destroyed when it reacts with molecules containing nitrogen, hydrogen, chlorine or bromine.
Some of these chemicals are also found in nature, but the halogen-containing chemicals we produce are responsible for the drastic decrease in ozone concentration. Their collective name is: Ozone Depleting Substances (ODS), i.e. substances that destroy the ozone layer. One of the most important of these substances are CFCs – chlorofluorocarbons. In the past, we used these in aerosol nozzles, refrigerators, air conditioners, fire extinguishers, among others.
By the way, the chlorine-methane released into the atmosphere during forest fires and the decomposition of trees is also an ozone-depleting substance.
The destruction of these substances by ultraviolet radiation initiates chemical chain reactions that support, for example, the removal of nitrogen compounds from chlorine, which moderate its destructive effect, thereby catalysing the destruction of the ozone layer. As a result, many more ozone molecules are destroyed than can be created by ultraviolet radiation.
A single chlorine molecule can break down 100,000 ozone molecules.
Effect – counter-effect – The importance of the polar circles
Since most of the above-mentioned substances enter through clouds at the polar circles, this is where the ozone layer is the thinnest and most vulnerable. Because of this, a greater amount of ultraviolet radiation reaches these areas, which accelerates the melting. The accelerated, large amount of melting results in even more water vapour, which increases the greenhouse effect and average temperature of our planet even more.
By the way, the stratosphere is shrinking due to the emission of greenhouse gases (mainly carbon dioxide) such as water vapour and the thinning of the ozone layer. While this causes warming in the troposphere, it causes cooling in the stratosphere. As a result, the troposphere expands, pushing the lower layer of the stratosphere, the tropopause, higher and higher, while its upper layer, the stratopause, shifts downward.
The stratosphere is 400 meters thinner than in 1980.
100 meters per decade.
So, the ozone layer is actually not getting holes, but is thinning, which allows more and more ultraviolet radiation to enter, and although this radiation only penetrates the body covering of living beings, it causes serious changes in their bodies, it does not “only” harm our planet. For us humans, for example, it can cause skin cancer.
In nature, the marine ecosystem is noticeably threatened by harmful ultraviolet radiation, starting with plankton, which for example is the food of whale species. The disruption of the marine (and any other) ecosystem affects all living things on Earth.
Ultraviolet radiation
It mainly comes to us from the Sun, but can also be created by lightning storm, and it can also be produced artificially. We distinguish between 3 types:
UV-A: most of the radiation that reaches us comes from this range. It is constantly present, it passes through (general) windows, clouds, etc. This is responsible for the aging of the skin and the development of skin cancer (this radiation can destroy the DNA itself). It burns, only tans in the short term.
UV-B: helps our body to produce vitamin D, it makes us tan in the long run. Its strength varies, it is mostly strong in the midday hours and passes filtered through the clouds. This radiation can also damage the eyes, not just the skin.
UV-C: only pilots and astronauts “meet” this kind of radiation. Our earth’s atmosphere filters it out. Sterilizing, highly carcinogenic. One of the chemical-free, environmentally friendly methods of disinfection is, for example, the UVC lamp, which is increasingly used by professionals.
Some living being sees in the ultraviolet range, like bees for example.
Montreal Protocol and the Paris Climate Agreement
On 16th September 1987, 46 countries signed the Montreal Protocol containing prohibitive prohibition the production and use of harmful substances. Today, 196 countries are part of it, and this day has become World Ozone Day.
At the international level, the 2016 Paris Agreement formulates various commitments to reduce the emission of greenhouse gases, such as: keeping the increase in the global average temperature below 2 °C. The level of contribution varies from country to country, but the convention itself was signed by 195 countries.
In December 2020, the European Union decided that by 2030, a net reduction of at least 55% of greenhouse gas emissions within the EU should be achieved compared to the 1990 level.
Present
Based on the most recent study, the Scientific-Assessment-of-Ozone-Depletion (you can read it HERE): since than the introduction and observance of the various climate protection conventions the state of the ozone layer/ozone hole near the polar circles, has been constantly regenerating. This survey is prepared every quarter on behalf of the United Nations.
METEOROLOGICAL/WEATHER BALLOON
The balloon is a carrying device. For this, the measuring devices and the radiosonde are fixed, which is necessary for the transmission of weather data. The balloon is filled with helium or hydrogen, that’s why it can rise to a height of 23-30 km. This rise lasts for 75-80 minutes and during this time it broadcasts the measured data. Up there, the balloon expands to a diameter of 12 meters. After a while, the material cannot withstand the low air pressure and the cold, so it bursts. In such cases, he returns with the instruments by free fall or parachutes.
Air pressure, humidity, temperature, light pollution, even the effects of cosmic radiation and the composition of aircraft contrails are measured in this way.
The stratosphere is the most special atmosphere of our Little Blue.
Be a Nerdy Bird!
