CG: n

CT: Satellite-borne IR radiometers are turning the Earth’s stratosphere into one of the best available outdoor laboratories for observing the large-scale dynamics of a rotating, heterogeneous fluid under gravity. New insight is being gained not only into stratospheric dynamics as such, with its implications for pollutant behaviour and the ozone layer, but also indirectly into the dynamics of the troposphere, with its implications for weather forecasting. Similar dynamical regimes occur in the oceans and in stellar interiors.

S: MP – [PDF] (p. 593) (last access: 14 January 2021)

N: 1. 1908, from French stratosphère, “sphere of layers,” from Latin stratus “a spreading out” (from past participle stem of sternere “to spread out,”) and French -sphère, as in atmosphère, which was coined by French meteorologist Léon-Philippe Teisserenc de Bort.
2. The stratosphere is the part of the Earth’s atmosphere which extends from the top of the troposphere to about 50 kilometers (30 miles) above the surface and in which temperature increases gradually to about 0° C (32° F) and clouds rarely form.
3. The stratosphere is a layer of Earth’s atmosphere. It is the second layer of the atmosphere as you go upward. The stratosphere is situated above the troposphere and under the mesosphere.
4. A rare type of electrical discharge, somewhat akin to lightning, occurs in the stratosphere. These “blue jets” appear above thunderstorms, and extend from the bottom of the stratosphere up to altitudes of 40 to 50 kilometers (25 to 31 miles).
5. Due to the fact that the stratosphere is very dry, the air there contains little water vapor. For this reason most clouds form within troposphere. Nevertheless, polar stratospheric clouds (PSCs) are the exception. PSCs appear in the lower stratosphere near the poles in winter. They are found at altitudes of 15 to 25 kilometers (9.3 to 15.5 miles) and form only when temperatures at those heights dip below -78° C (-108.4° F).
6. There are no storms or turbulence within the stratosphere. Commercial passenger jets fly in the lower stratosphere, partly because this layer provides a smoother ride. This is due to the air and the way it varies from the bottom to the start of the stratosphere. It is the opposite of how the layers work in the troposphere – where it gets colder the higher you go. Therefore, in the stratosphere it gets hotter the higher you go.
7. The stratosphere is 35 kilometers (22 miles) thick and represents a very important element of the important ozone layer as it protects the Earth from ultraviolet radiation (UV) from the sun.
8. The troposphere and the stratosphere are separated by a boundary called the tropopause, whose altitude varies from about 16 kilometers in the tropics to about 8 kilometers near the poles.
9. The climatology, seasonal evolution, and variability of the stratospheric circulation are strongly governed by the combined influences of solar and infrared radiation, ozone chemistry, and gravity waves that propagate upward from the troposphere below. While it contains a smaller fraction of atmospheric mass than the troposphere, the stratosphere is far from being a passive bystander to tropospheric influences.
10. The stratosphere is often referred to as the “ozone layer,” because of the relatively high concentrations produced by photochemical reactions in this region of the atmosphere. Although the stratosphere represents a part of the ozone and therefore should not be mistaken as the same thing.
The most beautiful “nacreous clouds” or “polar stratospheric clouds” are formed 19 kilometers (12 miles) above the stratosphere and they were only commonly visible to those at the highest latitudes, such as Mawson station, in Antarctica. Now, they can be observed across much of Britain,  Scotland and as far south as the Midlands. More nacreous clouds appear during colder winters, which lead to a greater subsequent depletion of ozone. The general increase in observations of these clouds is considered by some scientists as linked to man’s contribution to global warming.

S: 1. OED – (last access: 14 January 2021). 2. MW – (last access: 14 January 2021). 3 to 5. UCAR – (last access: 14 January 2021). 6. NASA – (last access: 14 January 2021); UCAR – (last access: 14 January 2021). 7. NASA – (last access: 14 January 2021). 8 to 10. SDir – (last access: 14 January 2021). 11. The Guardian – (last access: 14 January 2021).


CR: air pollution, biome, biosphere, carbon dioxidecarbon monoxide, chlorofluorocarbon, climate change, CO2 emissions, contaminant, ecology, environment, global warminggreenhouse effect, greenhouse gas, hydrocarbon, ionosphere, mesopause, mesosphere, meteor shower, methane, nitrogen dioxide, nitrogen oxide, nitrous oxide, ozone layer, pollutionpreservation of biodiversity, stratospheric ozone, sulfur dioxide, tropospheric ozone.