Isaac Meyer Held (born 1948) is an American meteorologist. He is a senior research scientist at the

Geophysical Fluid Dynamics Laboratory The Geophysical Fluid Dynamics Laboratory (GFDL) is a laboratory in the National Oceanic and Atmospheric Administration (NOAA) Office of Oceanic and Atmospheric Research (OAR). The current director is Dr. Venkatachalam Ramaswamy. It is one of se ...

. Held was elected to the

United States National Academy of Sciences The National Academy of Sciences (NAS) is a United States nonprofit, non-governmental organization. NAS is part of the National Academies of Sciences, Engineering, and Medicine, along with the National Academy of Engineering (NAE) and the Nati ...

in 2003.

Biography

Born to refugee parents in Ulm, Germany in 1948, Held came to Minnesota with his family at the age of 4. His father died when he was only eight and he and his brother were raised by his mother Bertha, a Holocaust survivor who worked as a seamstress. Held did his undergraduate work in physics at the University of Minnesota, Minneapolis in 1969 and started a graduate program in theoretical physics at the State University of New York at Stony Brook. While there, he discovered climate science which led to his transferring to the Atmospheric and Oceanic Sciences Program at

Princeton University Princeton University is a private university, private research university in Princeton, New Jersey. Founded in 1746 in Elizabeth, New Jersey, Elizabeth as the College of New Jersey, Princeton is the List of Colonial Colleges, fourth-oldest ins ...

, where he completed his Ph.D. in 1976 under the supervision of

Syukuro Manabe is a Japanese-American meteorologist and climatologist who pioneered the use of computers to simulate global climate change and natural climate variations. He was awarded the 2021 Nobel Prize in Physics jointly with Klaus Hasselmann and Giorg ...

. After a brief stint as a postdoctoral fellow at

Harvard University Harvard University is a private Ivy League research university in Cambridge, Massachusetts. Founded in 1636 as Harvard College and named for its first benefactor, the Puritan clergyman John Harvard, it is the oldest institution of higher le ...

, Held returned to Princeton to join the

in 1978. He is currently a senior research scientist at the laboratory and teaches in the Atmospheric and Oceanic Sciences Program at Princeton University.

Research

Held's research has had two major themes. The first is understanding how the earth's climate responds to changes in the amount of solar radiation hitting the planet or to the concentration of greenhouse gasses in the atmosphere. His early work highlighted the importance of the

lapse rate The lapse rate is the rate at which an atmospheric variable, normally temperature in Earth's atmosphere, falls with altitude. ''Lapse rate'' arises from the word ''lapse'', in the sense of a gradual fall. In dry air, the adiabatic lapse rate is ...

in determining the climate's response to radiation changes. Held has continued to be concerned with how global warming can alter both the cycle of water and the distribution of winds on earth. In a paper published in 2006 with Brian Soden, he showed that this increase in precipitation might nonetheless be associated with a slowdown of the

Walker circulation The Walker circulation, also known as the Walker cell, is a conceptual model of the air flow in the tropics in the lower atmosphere (troposphere). According to this model, parcels of air follow a closed circulation in the zonal and vertical dir ...

. The second theme of Held's research is the general circulation of the atmosphere. In one of his earliest papers, he showed that when a region is unstable to the large-scale planetary waves known as

Rossby waves Rossby waves, also known as planetary waves, are a type of inertial wave naturally occurring in rotating fluids. They were first identified by Sweden-born American meteorologist Carl-Gustaf Arvid Rossby. They are observed in the atmospheres and ...

, the propagation of waves out of this region results in an easterly (westward) acceleration, which generates

jet streams Jet streams are fast flowing, narrow, meandering thermal wind, air currents in the Atmosphere of Earth, atmospheres of some planets, including Earth. On Earth, the main jet streams are located near the altitude of the tropopause and are west ...

in midlatitudes. In contrast, regions in which these waves break experience an eastward (westerly) acceleration. Held also developed a theory for the

Hadley circulation The Hadley cell, named after George Hadley, is a global-scale tropical atmospheric circulation that features air rising near the equator, flowing poleward at a height of 10 to 15 kilometers above the earth's surface, descending in the subtropics, ...

that would exist in the absence of atmospheric turbulence.

Awards and honors

*1987: Clarence Leroy Meisinger Award,

American Meteorological Society The American Meteorological Society (AMS) is the premier scientific and professional organization in the United States promoting and disseminating information about the Atmospheric sciences, atmospheric, Oceanography, oceanic, and Hydrology, hydr ...

*1991: Fellow,

*1995: Fellow,

American Geophysical Union The American Geophysical Union (AGU) is a 501(c)(3) nonprofit organization of Earth, atmospheric, ocean, hydrologic, space, and planetary scientists and enthusiasts that according to their website includes 130,000 people (not members). AGU's act ...

*2003: Elected to the

*2008:

Carl-Gustaf Rossby Research Medal 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- ...

*2011:

BBVA Foundation Frontiers of Knowledge Award The BBVA Foundation Frontiers of Knowledge Awards () are an international award programme recognizing significant contributions in the areas of scientific research and cultural creation. The categories that make up the Frontiers of Knowledge Awards ...

of Climate Change for his fundamental and pioneering contributions to our understanding of the structure of atmospheric circulation systems, and the role of water vapor – the most important greenhouse gas – in Climate Change. *2018:

Roger Revelle Medal The Roger Revelle Medal is given out annually by the American Geophysical Union to recognize "outstanding accomplishments or contributions toward the understanding of the Earth’s atmospheric processes, including its dynamics, chemistry, and r ...

References

External links

Isaac Held's Homepage
at the Geophysical Fluid Dynamics Laboratory.
Isaac Held's bibliography
at the Geophysical Fluid Dynamics Laboratory.
Isaac Held's blog
at the Geophysical Fluid Dynamics Laboratory. {{DEFAULTSORT:Held, Isaac University of Minnesota College of Science and Engineering alumni American meteorologists American people of German-Jewish descent Intergovernmental Panel on Climate Change lead authors National Oceanic and Atmospheric Administration personnel Living people Members of the United States National Academy of Sciences Fellows of the American Geophysical Union 1948 births

Biography

Research

Awards and honors

See also

References

External links