Graeme Stephens

Last updated

Graeme Stephens
FRS
Graeme Stephens at JPL in by christopher michel 04.jpg
Graeme Stephens in 2021
Born
Graeme Leslie Stephens
Alma mater University of Melbourne (BS, PhD) [1]
Known for CloudSat [2]
Awards Jule G. Charney Award (2005)
Scientific career
Fields Atmospheric sciences
Institutions Caltech
Colorado State University [3]
University of Reading
University of Melbourne
Thesis The transfer of radiation in cloudy atmospheres  (1977)
Website science.jpl.nasa.gov/people/Stephens

Graeme Leslie Stephens FRS [4] is director of the center for climate sciences at the NASA Jet Propulsion Laboratory at the California Institute of Technology [5] and professor of earth observation the University of Reading. [6] [7]

Contents

Education

Stephens was educated at the University of Melbourne in Australia where he received a Bachelor of Science degree in Physics 1973 in followed by a PhD in meteorology in 1977. [1]

Career and research

Stephens research has provided leadership in three major disciplinary areas of Earth sciences:

  1. Atmospheric radiation and radiative transfer [4]
  2. Earth observations and remote sensing [4]
  3. Understanding critical cloud-climate feedbacks and related effects on the Earth's energy budget [4]

Stephens has pioneered quantitative uses of global Earth observations and combined this with theory to study Earth's climate change feedback. [4] He provided leadership in designing and developing international satellite programs exemplified by his creation and leadership of the decade long CloudSat satellite mission [2] that is providing novel insights and understanding of the Earth's clouds, precipitation and their role in climate. [4] [3] [8]

Awards and honours

Stephens was elected a member of the National Academy of Engineering of the United States in 2015, [4] received the Jule G. Charney Award of the American Meteorological Society for pioneering advances in understanding and measuring radiation processes and their role in climate, and received the Gold Medal of the International Radiation Commission in recognition of world leading contributions to the radiation community. [4] He also received National Aeronautics Space Administration, Exceptional Public Service Medal. [4] In 2025 he received the Carl-Gustaf Rossby Research Medal of the American Meteorological Society. [9]

He was elected a Fellow of the Royal Society in 2018. [4]

Related Research Articles

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<span class="mw-page-title-main">Climate model</span> Quantitative methods used to simulate climate

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<span class="mw-page-title-main">Cloud feedback</span> Type of climate change feedback mechanism

Cloud feedback is a type of climate change feedback, where the overall cloud frequency, height, and the relative fraction of the different types of clouds are altered due to climate change, and these changes then affect the Earth's energy balance. On their own, clouds are already an important part of the climate system, as they consist of water vapor, which acts as a greenhouse gas and so contributes to warming; at the same time, they are bright and reflective of the Sun, which causes cooling. Clouds at low altitudes have a stronger cooling effect, and those at high altitudes have a stronger warming effect. Altogether, clouds make the Earth cooler than it would have been without them.

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The Carl-Gustaf Rossby Research Medal is the highest award for atmospheric science of the American Meteorological Society. It is presented to individual scientists, who receive a medal. Named in honor of meteorology and oceanography pioneer Carl-Gustaf Rossby, who was also its second (1953) recipient.

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Nephology is the study of clouds and cloud formation. British meteorologist Luke Howard was a major researcher within this field, establishing a cloud classification system. While this branch of meteorology still exists today, the term nephology, or nephologist is rarely used. The term came into use at the end of the nineteenth century, and fell out of common use by the middle of the twentieth. Recently, interest in nephology has increased as some meteorologists have begun to focus on the relationship between clouds and global warming, which is a source of uncertainty regarding "estimates and interpretations of the Earth’s changing energy budget."

<span class="mw-page-title-main">Earth's energy budget</span> Concept for energy flows to and from Earth

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A runaway greenhouse effect will occur when a planet's atmosphere contains greenhouse gas in an amount sufficient to block thermal radiation from leaving the planet, preventing the planet from cooling and from having liquid water on its surface. A runaway version of the greenhouse effect can be defined by a limit on a planet's outgoing longwave radiation which is asymptotically reached due to higher surface temperatures evaporating water into the atmosphere, increasing its optical depth. This positive feedback means the planet cannot cool down through longwave radiation and continues to heat up until it can radiate outside of the absorption bands of the water vapour.

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References

  1. 1 2 Stephens, Graeme Leslie (1977). The transfer of radiation in cloudy atmospheres (PhD thesis). University of Melbourne. OCLC   220235247.
  2. 1 2 Stephens, Graeme L.; Vane, Deborah G.; Boain, Ronald J.; Mace, Gerald G.; Sassen, Kenneth; Wang, Zhien; Illingworth, Anthony J.; O'connor, Ewan J.; Rossow, William B.; Durden, Stephen L.; Miller, Steven D.; Austin, Richard T.; Benedetti, Angela; Mitrescu, Cristian (2002). "THE CLOUDSAT MISSION AND THE A-TRAIN: A New Dimension of Space-Based Observations of Clouds and Precipitation". Bulletin of the American Meteorological Society. 83 (12): 1771–1790. doi: 10.1175/BAMS-83-12-1771 . ISSN   0003-0007. Open Access logo PLoS transparent.svg
  3. 1 2 Stephens, Graeme L.; Tsay, Si-Chee; Stackhouse, Paul W.; Flatau, Piotr J. (1990). "The Relevance of the Microphysical and Radiative Properties of Cirrus Clouds to Climate and Climatic Feedback". Journal of the Atmospheric Sciences. 47 (14): 1742–1754. Bibcode:1990JAtS...47.1742S. doi: 10.1175/1520-0469(1990)047<1742:TROTMA>2.0.CO;2 . ISSN   0022-4928.
  4. 1 2 3 4 5 6 7 8 9 10 Anon (2018). "Professor Graeme Stephens FRS". London: Royal Society. One or more of the preceding sentences incorporates text from the royalsociety.org website where:
    “All text published under the heading 'Biography' on Fellow profile pages is available under Creative Commons Attribution 4.0 International License.” -- "Terms, conditions and policies | Royal Society". Archived from the original on 11 November 2016. Retrieved 27 June 2018.{{cite web}}: CS1 maint: bot: original URL status unknown (link)
  5. Stephens, Graeme. "Science - Center for Climate Sciences (3292): People: Graeme Stephens". science.jpl.nasa.gov.
  6. Reading, The University of. "Graeme Stephens Home Page". www.met.reading.ac.uk.
  7. Graeme Stephens publications indexed by the Scopus bibliographic database. (subscription required)
  8. Stephens, Graeme L. (2005). "Cloud Feedbacks in the Climate System: A Critical Review". Journal of Climate. 18 (2): 237–273. Bibcode:2005JCli...18..237S. doi: 10.1175/JCLI-3243.1 . ISSN   0894-8755. S2CID   16122908.
  9. Carl-Gustaf Rossby Research Medal 2025

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