Saiz-Lopez Receives 2007 Holton Award

Alfonso Saiz-Lopez received the 2007 James R. Holton Junior Scientist Award at the 2007 AGU Fall Meeting in San Francisco, Calif. The award recognizes outstanding research contributions by a junior atmospheric scientist within 3 years of his or her Ph.D.


saiz-lopez_alfonsoAlfonso Saiz-Lopez has quickly become a rising star in halogen chemistry, a subject first brought to public attention in connection with the ozone hole over Antarctica. The ozone hole is related to stratospheric halogen chemistry, while Saiz-Lopez’s work is mainly concerned with tropospheric halogen chemistry. Saiz-Lopez has done an impressive amount of fundamental work to address this issue, ranging from experimental work to satellite data analysis to modeling, leading to 12 first-authored papers and a total of 33 publications to his credit. This is exceptional for someone who completed his thesis only 2 years ago.

The general focus of his research has been the chemistry of iodine, to which he has made four important contributions. First, he showed that the major source of molecular iodine (I2) is biogenic emission; previously, scientists thought that the source was organic iodine species. Second, he showed that these I2 emissions are high enough to generate huge amounts of ultrafine aerosol particles. Third, he discovered completely unexpected concentrations of IO [iodine oxide] in the Antarctic coastal region. IO causes substantial ozone depletion and the rapid oxidation of dimethyl sulfide, a gas released by plankton and implicated in cloud changes over plankton blooms. He found the highest levels of IO ever recorded in the atmosphere. Fourth, he made the first satellite observations of the IO radical over the Antarctic and showed they are higher over Antarctic sea ice than near the coast.

Alfonso Saiz-Lopez has made these outstanding contributions through his own remarkable abilities, as well as through unselfish collaboration with a large number of people at universities and research institutes in Europe and the United States.

Warren J. Wiscombe, NASA Goddard Space Flight Center, Greenbelt, Md.


I am honored and humbled to be the recipient of this prestigious award. It is particularly inspiring since the award bears the name of someone whose career was as exceptional as James Holton’s was.

Over the years I have been privileged to have a number of fantastic mentors including John Plane, Stanley Sander, and Kelly Chance, whose guidance, support, and advice have been instrumental in my short career. I am also fortunate to have worked with a number of outstanding collaborators who, through their exceptional work ethic and their generous spirit, represent the epitome of good science and teamwork.

As an atmospheric scientist, I get the fortunate opportunity to examine, sometimes in minute detail, the intricacies of the planet on which we live. To be able to contribute to our fundamental understanding of Earth’s processes is my life’s work, and this recognition is most rewarding. I am very grateful to the AGU Atmospheric Sciences section for the great honor of receiving this award, and I hope I can live up to it.

Alfonso Saiz-Lopez, NASA, Pasadena, Calif.