|Died||January 2, 2015 85) (aged|
Kensington, California, U.S.
|Alma mater||University of Belgrade|
Tihomir Novakov, Ph.D known also as Tica Novakov (March 16, 1929 – January 2, 2015) was a Serbian-born American physicist. As a scientist, Novakov is known for his black carbon, air quality, and climate change research. James Hansen dubbed him "the godfather of black carbon".
Novakov was born in Sombor, Serbia, in 1929. His father was a veterinarian and his mother was a homemaker. While in high school, Novakov began to build X-ray tubes and radios, furthering his scientific knowledge on his own.
After graduating from the University of Belgrade with a PhD in nuclear physics, he taught at the University of Belgrade and worked at the Vinča Nuclear Institute. Novakov migrated to the United States in 1963 and began working as a research scientist at the Lawrence Berkeley National Laboratory. He later founded an Aerosol Research Group which traveled the world conducting research on climate change.
In the late 1960s and early 1970s, Novakov's group was the first to apply X-ray photoelectron and Raman spectroscopy to samples of atmospheric aerosols, which helped to establish the existence of a large elemental or soot fraction and provided definitive identification of physical structures similar to graphite and activated carbon in urban and remote aerosols, including in the Arctic. Following these discoveries, Novakov coined the term "black carbon" to refer to the sunlight absorbing portion of ambient particulate matter. Novakov’s aerosol research group, which included Hal Rosen, Ted Chang, Anthony Hansen, Ray Dod and Lara Gundel, developed new analytical techniques for measuring black carbon, the most notable of which is the aethalometer. The aethalometer, the name of which is derived from a Greek word that means "to blacken with soot", is today the mostly widely used instrument worldwide for measuring atmospheric concentrations of black carbon. Novakov hosted the first International Conference on Carbonaceous Particles in the Atmosphere at LBNL in 1978 to provide a forum for scientists to discuss this emerging research field. The conference series continues today alternating every few years between Berkeley and Vienna.
Novakov was a distinguished member of the Serbian Academy of Sciences and Arts.
Novakov has had his work published hundreds of times in peer-reviewed journals and his work has been cited in over 6,000 articles. In October 1974, Science published "Sulfates as pollution particulates: catalytic formation on carbon (soot) particles", which Novakov co-wrote with S. G. Chang and A. B. Harker.In 1984, "The Aethalometer – an instrument for the real-time measurement of optical-absorption by aersosol-particles", co-written with Anthony Hansen and Hal Rosen, was published in Science of the Total Environment . "Large contribution of organic aerosols to cloud-condensation nuclei concentrations", co-written with Joyce Penner, was published by Nature in 1993. "Evidence that the spectral dependence of light absorption by aerosols is affected by organic carbon", written by Thomas Kirchstetter, Novakov, and Peter Hobbs, was published in Journal of Geophysical Research in 2004. Novakov's final publication, "The black carbon story: early history and new perspectives", co-written with Rosen, was published in Ambio in 2013.
Novakov was married to Marica Cvetković from 1954 until her death in 2014. The couple had a daughter, Anna Novakov, now an art history professor at Saint Mary's College of California.
Novakov died on January 2, 2015, in Kensington, California from natural causes, aged 85.
Nuclear winter is a severe and prolonged global climatic cooling effect that is hypothesized to occur after widespread firestorms following a large-scale nuclear war. The hypothesis is based on the fact that such fires can inject soot into the stratosphere, where it can block some direct sunlight from reaching the surface of the Earth. It is speculated that the resulting cooling would lead to widespread crop failure and famine. When developing computer models of nuclear-winter scenarios, researchers use the conventional bombing of Hamburg, and the Hiroshima firestorm in World War II as example cases where soot might have been injected into the stratosphere, alongside modern observations of natural, large-area wildfire-firestorms.
Smoke is a suspension of airborne particulates and gases emitted when a material undergoes combustion or pyrolysis, together with the quantity of air that is entrained or otherwise mixed into the mass. It is commonly an unwanted by-product of fires, but may also be used for pest control (fumigation), communication, defensive and offensive capabilities in the military, cooking, or smoking. It is used in rituals where incense, sage, or resin is burned to produce a smell for spiritual or magical purposes. It can also be a flavoring agent and preservative.
An aerosol is a suspension of fine solid particles or liquid droplets in air or another gas. Aerosols can be natural or anthropogenic. Examples of natural aerosols are fog or mist, dust, forest exudates, and geyser steam. Examples of anthropogenic aerosols include particulate air pollutants, mist from the discharge at hydroelectric dams, irrigation mist, perfume from atomizers, smoke, dust, steam from a kettle, sprayed pesticides, and medical treatments for respiratory illnesses. When a person inhales the contents of a vape pen or e-cigarette, they are inhaling an anthropogenic aerosol.
The first systematic measurements of global direct irradiance at the Earth's surface began in the 1950s. A decline in irradiance was soon observed, and it was given the name of global dimming. It continued from 1950s until 1980s, with an observed reduction of 4–5% per decade, even though solar activity did not vary more than the usual at the time. Global dimming has instead been attributed to an increase in atmospheric particulate matter, predominantly sulfate aerosols, as the result of rapidly growing air pollution due to post-war industrialization. After 1980s, global dimming started to reverse, alongside reductions in particulate emissions, in what has been described as global brightening, although this reversal is only considered "partial" for now. The reversal has also been globally uneven, as the dimming trend continued during the 1990s over some mostly developing countries like India, Zimbabwe, Chile and Venezuela. Over China, the dimming trend continued at a slower rate after 1990, and did not begin to reverse until around 2005.
Tholins are a wide variety of organic compounds formed by solar ultraviolet or cosmic ray irradiation of simple carbon-containing compounds such as carbon dioxide, methane or ethane, often in combination with nitrogen or water. Tholins are disordered polymer-like materials made of repeating chains of linked subunits and complex combinations of functional groups, typically nitriles and hydrocarbons and their degraded forms such as amines and phenyls. Tholins do not form naturally on modern-day Earth, but they are found in great abundance on the surfaces of icy bodies in the outer Solar System, and as reddish aerosols in the atmospheres of outer Solar System planets and moons.
Soot is a mass of impure carbon particles resulting from the incomplete combustion of hydrocarbons. It is more properly restricted to the product of the gas-phase combustion process but is commonly extended to include the residual pyrolysed fuel particles such as coal, cenospheres, charred wood, and petroleum coke that may become airborne during pyrolysis and that are more properly identified as cokes or char.
Cloud condensation nuclei (CCNs), also known as cloud seeds, are small particles typically 0.2 µm, or one hundredth the size of a cloud droplet. CCNs are a unique subset of aerosols in the atmosphere on which water vapour condenses. This can affect the radiative properties of clouds and the overall atmosphere. Water requires a non-gaseous surface to make the transition from a vapour to a liquid; this process is called condensation.
Chemically, black carbon (BC) is a component of fine particulate matter. Black carbon consists of pure carbon in several linked forms. It is formed through the incomplete combustion of fossil fuels, biofuel, and biomass, and is one of the main types of particle in both anthropogenic and naturally occurring soot. Black carbon causes human morbidity and premature mortality. Because of these human health impacts, many countries have worked to reduce their emissions, making it an easy pollutant to abate in anthropogenic sources.
Mark Zachary Jacobson is a professor of civil and environmental engineering at Stanford University and director of its Atmosphere/Energy Program. He is also a co-founder of the non-profit, Solutions Project.
Particulates or atmospheric particulate matter are microscopic particles of solid or liquid matter suspended in the air. The term aerosol commonly refers to the particulate/air mixture, as opposed to the particulate matter alone. Sources of particulate matter can be natural or anthropogenic. They have impacts on climate and precipitation that adversely affect human health, in ways additional to direct inhalation.
An aethalometer is an instrument for measuring the concentration of optically absorbing (‘black’) suspended particulates in a gas colloid stream; commonly visualized as smoke or haze, often seen in ambient air under polluted conditions. The word aethalometer is derived from the Classical Greek verb aethaloun, meaning "to blacken with soot". The aethalometer, a device used for measuring black carbon in atmospheric aerosols, was initially deployed in 1980 and was first commercialized by Magee Scientific.
Tami Bond holds the Walter Scott, Jr. Presidential Chair in Energy, Environment and Health at Colorado State University since 2019. For many years she was a professor of Civil and Environmental Engineering at the University of Illinois, and an affiliate professor of Atmospheric Science. Bond has focused research on the effective study of black carbon or soot in the atmosphere. She is a Fellow of the American Geophysical Union. A MacArthur Fellowship was awarded to her in 2014.
Barbara J. Finlayson-Pitts is a Canadian-American atmospheric chemist. She is a professor in the chemistry department at the University of California, Irvine and is the Director of AirUCI Institute. Finlayson-Pitts and James N. Pitts, Jr. are the authors of Chemistry of the Upper and Lower Atmosphere: Theory, Experiments, and Applications (1999). She has been a member of the National Academy of Sciences since 2006 and is the laureate for the 2017 Garvan–Olin Medal. In 2016 she co-chaired the National Academy of Science report "The Future of Atmospheric Chemistry Research"
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Roy Michael Harrison is a British environmental scientist. He has been Queen Elizabeth II Birmingham Centenary Professor of Environmental Health at the University of Birmingham since 1991, and is a distinguished adjunct professor at King Abdulaziz University in Jeddah, Saudi Arabia.
Kimberly A. Prather is an American atmospheric chemist. She is a distinguished chair in atmospheric chemistry and a distinguished professor at the Scripps Institution of Oceanography and department of chemistry and biochemistry at UC San Diego. Her work focuses on how humans are influencing the atmosphere and climate. In 2019, she was elected a member of the National Academy of Engineering for technologies that transformed understanding of aerosols and their impacts on air quality, climate, and human health. In 2020, she was elected as a member of the National Academy of Sciences. She is also an elected Fellow of the American Philosophical Society, American Geophysical Union, the American Association for the Advancement of Science, American Philosophical Society, and the American Academy of Arts and Sciences.
Lynn Russell is a professor of atmospheric chemistry at the Scripps Institute of Oceanography a division of the University of California, San Diego in La Jolla, California.
Hugh Coe is a British atmospheric physicist, currently Head of Atmospheric Sciences and Professor of Atmospheric Composition at the University of Manchester. His research investigates the physics and chemistry of atmospheric aerosols, including their role in climate change and air pollution.