OrbitalHub

Wikipedia dixit:

“The ozone layer or ozone shield is a region of Earth’s stratosphere that absorbs most of the Sun’s ultraviolet radiation. It contains high concentrations of ozone (O3) in relation to other parts of the atmosphere, although still small in relation to other gases in the stratosphere. The ozone layer contains less than 10 parts per million of ozone, while the average ozone concentration in Earth’s atmosphere as a whole is about 0.3 parts per million. The ozone layer is mainly found in the lower portion of the stratosphere, from approximately 20 to 30 kilometers (12 to 19 mi) above Earth, although its thickness varies seasonally and geographically.

The ozone layer was discovered in 1913 by the French physicists Charles Fabry and Henri Buisson. Measurements of the sun showed that the radiation sent out from its surface and reaching the ground on Earth is usually consistent with the spectrum of a black body with a temperature in the range of 5,500–6,000 K (5,227 to 5,727 °C), except that there was no radiation below a wavelength of about 310 nm at the ultraviolet end of the spectrum. It was deduced that the missing radiation was being absorbed by something in the atmosphere. Eventually the spectrum of the missing radiation was matched to only one known chemical, ozone. Its properties were explored in detail by the British meteorologist G. M. B. Dobson, who developed a simple spectrophotometer (the Dobsonmeter) that could be used to measure stratospheric ozone from the ground. Between 1928 and 1958, Dobson established a worldwide network of ozone monitoring stations, which continue to operate to this day. The “Dobson unit”, a convenient measure of the amount of ozone overhead, is named in his honor.

The ozone layer absorbs 97 to 99 percent of the Sun’s medium-frequency ultraviolet light (from about 200 nm to 315 nm wavelength), which otherwise would potentially damage exposed life forms near the surface.

In 1976 atmospheric research revealed that the ozone layer was being depleted by chemicals released by industry, mainly chlorofluorocarbons (CFCs). Concerns that increased UV radiation due to ozone depletion threatened life on Earth led to bans on the chemicals, and the latest evidence is that ozone depletion has slowed or stopped. “

Credits Video: ESA

ESA dixit:

“See in this time-lapse how the Sentinel-3B satellite was prepared for its liftoff on 25 April 2018 from Plesetsk in Russia.

Sentinel-3B joined its twin, Sentinel-3A, in orbit. The pairing of identical satellites provides the best coverage and data delivery for Europe’s Copernicus programme – the largest environmental monitoring programme in the world. The satellites carry the same suite of cutting-edge instruments to measure oceans, land, ice and atmosphere.”

Credits Video: ESA/Stephane Corvaja/Zetapress/Manuel Pedoussaut/Hubrid-Rockot

NASA dixit:

“Earth’s energy budget is a metaphor for the delicate equilibrium between energy received from the Sun versus energy radiated back out in to space. Research into precise details of Earth’s energy budget is vital for understanding how the planet’s climate may be changing, as well as variabilities in solar energy output.

Missions like NASA’s TSIS will help scientists keep a close watch. NASA’s Total and Spectral Solar Irradiance Sensor, or TSIS-1, is a mission to measure the sun’s energy input to Earth. Various satellites have captured a continuous record of this solar energy input since 1978. TSIS-1 sensors advance previous measurements, enabling scientists to study the sun’s natural influence on Earth’s ozone layer, atmospheric circulation, clouds, and ecosystems. These observations are essential for a scientific understanding of the effects of solar variability on the Earth system.

NASA Goddard Space Flight Center manages the project. The University of Colorado’s Laboratory for Atmospheric and Space Physics (LASP) built both instruments and provides mission operations. The International Space Station carries TSIS-1.”

Credits Video: NASA’s Goddard Space Flight Center/Michael Starobin

NASA dixit:

“GRACE Follow-On (GRACE-FO) is continuing GRACE’s legacy of tracking Earth’s water movement across the planet. Monitoring changes in ice sheets and glaciers, underground water storage, the amount of water in large lakes and rivers, and changes in sea level provides a unique view of Earth’s climate and has far-reaching benefits for its people.”

Credits Video: NASA

NASA dixit:

“Between 2002 and 2016, the Gravity Recovery and Climate Experiment (GRACE) tracked the movement of freshwater around the planet. NASA scientists used GRACE data to identify regional trends of freshwater movement, and combined that information with data from other satellites, climate models and precipitation measurements to determine the causes of major regional trends in freshwater storage.”

Credits Music: Iron Throne by Anthony Giordano [SACEM]

Credits Video: NASA’s Goddard Space Flight Center/Kathryn Mersmann

ESA dixit:

“Apart from Antarctica, Patagonia is home to the biggest glaciers in the southern hemisphere, but some are retreating faster than anywhere else in the world. This is because the weather is relatively warm and these glaciers typically terminate in fjords and lakes, exacerbating surface melting and causing them to flow faster and lose ice as icebergs at their margins. Traditionally, it has been very difficult to map exactly how fast these glaciers are changing. However, a new way of processing ESA CryoSat swath data now makes it possible to map these glaciers in fine detail. CryoSat has revealed that between 2011 and 2017, there was widespread thinning, particularly in Patagonia’s more northern ice fields. The Jorge Montt glacier, which flows down to the ocean, retreated 2.5 km and lost about 2.2 Gt a year. In contrast, Pio XI, the largest glacier in South America, advanced and gained mass at a rate of about 0.67 Gt a year. However, over the six-year period, the glaciers overall lost mass at a rate of over 21 Gt a year. This loss is adding about 0.06 mm a year to sea level.”

Video Credit: ESA