A sudden stratospheric warming (SSW) is an event in which polar stratospheric temperatures rise by several tens of kelvins over the course of a few days. The warming is preceded by a slowing then reversal of the westerly winds in the stratospheric polar vortex, commonly measured at 60 ° latitude at the 10 hPa level. SSWs occur about six times per decade in the northern hemisphere (NH), and about once every 20-30 years in the southern hemisphere (SH). In the SH, SSW accompanied by a reversal of the vortex westerly was observed once during the period 1979–2024; this was in September 2002. Stratospheric warming in September 2019 was comparable to or even greater than that of 2002, but the wind reversal did not occur.
Ground-level ozone (O3), also known as surface-level ozone and tropospheric ozone, is a trace gas in the troposphere (the lowest level of the Earth's atmosphere), with an average concentration of 20–30 parts per billion by volume (ppbv), with close to 100 ppbv in polluted areas. Ozone is also an important constituent of the stratosphere, where the ozone layer (2 to 8 parts per million ozone) exists which is located between 10 and 50 kilometers above the Earth's surface. The troposphere extends from the ground up to a variable height of approximately 14 kilometers above sea level. Ozone is least concentrated in the ground layer (or planetary boundary layer) of the troposphere. Ground-level or tropospheric ozone is created by chemical reactions between NOx gases (oxides of nitrogen produced by combustion) and volatile organic compounds (VOCs). The combination of these chemicals in the presence of sunlight form ozone. Its concentration increases as height above sea level increases, with a maximum concentration at the tropopause. About 90% of total ozone in the atmosphere is in the stratosphere, and 10% is in the troposphere. Although tropospheric ozone is less concentrated than stratospheric ozone, it is of concern because of its health effects. Ozone in the troposphere is considered a greenhouse gas, and may contribute to global warming.
MOPITT is an ongoing astronomical instrument aboard NASA's Terra satellite that measures global tropospheric carbon monoxide levels. It is part of NASA's Earth Observing System (EOS), and combined with the other payload remote sensors on the Terra satellite, the spacecraft monitors the Earth's environment and climate changes. Following its construction in Canada, MOPITT was launched into Earth's orbit in 1999 and utilizes gas correlation spectroscopy to measure the presence of different gases in the troposphere. The fundamental operations occur in its optical system composed of two optical tables holding the bulk of the apparatus. Results from the MOPITT enable scientists to better understand carbon monoxide's effects on a global scale, and various studies have been conducted based on MOPITT's measurements.
The atmosphere of Mars is the layer of gases surrounding Mars. It is primarily composed of carbon dioxide (95%), molecular nitrogen (2.85%), and argon (2%). It also contains trace levels of water vapor, oxygen, carbon monoxide, hydrogen, and noble gases. The atmosphere of Mars is much thinner and colder than Earth's having a max density 20g/m3 with a temperature generally below zero down to -60 Celsius. The average surface pressure is about 610 pascals (0.088 psi) which is 0.6% of the Earth's value.
The chemical equator term and concept was coined in 2008 when researchers from University of York discovered a distinct divide between the polluted air and haze over Indonesia from the largely uncontaminated atmosphere over Australia. This divide is distinguishable by a rapid increase in atmospheric levels of carbon monoxide and other pollutants from the Tropical Warm Pool region northward. The divide of the atmosphere of the northern hemisphere from the atmosphere of the southern hemisphere is different from that of the Intertropical Convergence Zone.
Lucy Jane Carpenter is a British chemist who is a professor of physical chemistry at the University of York and director of the Cape Verde Atmospheric Observatory (CVAO).
Roger Jay Phillips was an American geophysicist, planetary scientist, and professor emeritus at the Washington University in St. Louis. His research interests included the geophysical structure of planets, and the use of radar and gravity to investigate the surfaces and interiors of the planets.
Arlene M. Fiore is an atmospheric chemist whose research focuses on issues surrounding air quality and climate change.
Maura E. Hagan is a Professor Emeritus of Physics and a former Dean of the College of Science at Utah State University. She is a Fellow of both the American Meteorological Society and the American Geophysical Union, and was elected a member of the National Academy of Sciences in 2019.
Johannes "Jos" Lelieveld is a Dutch atmospheric chemist. Since 2000, he has been a Scientific Member of the Max Planck Society and director of the Atmospheric Chemistry Department at the Max Planck Institute for Chemistry in Mainz. He is also professor at the University of Mainz and at the Cyprus Institute in Nicosia.
Richard Mansergh Thorne was an American physicist and a distinguished professor in the department of atmospheric and oceanic sciences at UCLA. He was known for his contributions to space plasma physics. He was a fellow of the American Geophysical Union.
Sonia Maria Kreidenweis is an American Professor of Atmospheric Sciences at Colorado State University. Her research considers aerosols and their impact on weather and the climate. She has previously served as President of the American Association for Aerosol Research and was a board member of the American Meteorological Society. She was elected a Fellow of the American Geophysical Union in 2019.
William Henry Matthaeus is an American astrophysicist and plasma physicist. He is known for his research on turbulence in magnetohydrodynamics (MHD) and astrophysical plasmas, for which he was awarded the 2019 James Clerk Maxwell Prize for Plasma Physics.
Julia Yvonne Schmale is a German environmental scientist. She is a specialist in the micro-physical makeup of the atmosphere, in particular aerosols and their interaction with clouds. She is a professor at EPFL and the head of the Extreme Environments Research Laboratory (EERL). She is a participant in the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expeditions.
Lorraine Remer is research professor at University of Maryland, Baltimore County known for her work on developing algorithms to study aerosol particles using satellites with a particular focus on how aerosols impact climate processes.
Anne Ritger Douglass is atmospheric physicist known for her research on chlorinated compounds and the ozone layer.
Jennifer Logan is an atmospheric scientist known for her research on how human activities influence the atmosphere, particularly with respect to biomass burning and the ozone hole.
Patricia K. Quinn is an atmospheric chemist working at the National Oceanic and Atmospheric Agency's Pacific Marine Environmental Lab. She is known for her work on the impact of atmospheric aerosol particles on air quality and climate.
LuAnn Thompson is the Walters Endowed Professor at the University of Washington. She is known for her work in modeling the movement of heat and chemicals via ocean currents.
Randall V. Martin is a scientist, engineer, academic and author. He is the Raymond R. Tucker Distinguished Professor in the Department of Energy, Environmental, and Chemical Engineering, with a courtesy appointment in Computer Science and Engineering at Washington University in St. Louis, McKelvey School of Engineering.
