Iris hypothesis

The iris hypothesis was a hypothesis proposed by Richard Lindzen and colleagues in 2001 that suggested increased sea surface temperature in the tropics would result in reduced cirrus clouds and thus more infrared radiation leakage from Earth's atmosphere. His study of observed changes in cloud coverage and modeled effects on infrared radiation released to space as a result seemed to support the hypothesis.[1] This suggested infrared radiation leakage was hypothesized to be a negative feedback in which an initial warming would result in an overall cooling of the surface.

The idea of the iris effect of cirrus clouds in trapping outgoing radiation was reasonable, but it ignored the larger compensating effect on the blocking of incoming sun's rays, and effects of changes in altitude of clouds.[2]: 92 [3] Moreover, a number of errors were found in the papers.[4][5] For this reason, the iris effect no longer plays a role in the current scientific consensus on climate change.

  1. ^ Lindzen, Richard S.; Chou, Ming-Dah; Hou, Arthur Y. (2001). "Does the Earth have an adaptive infrared iris?" (PDF). Bull. Amer. Meteor. Soc. 82 (3): 417–432. Bibcode:2001BAMS...82..417L. doi:10.1175/1520-0477(2001)082<0417:DTEHAA>2.3.CO;2. hdl:2060/20000081750.
  2. ^ Trenberth, K. E. (2023). A personal tale of the development of Climate Science. The life and times of Kevin Trenberth. ISBN 978-0-473-68694-9.
  3. ^ Cite error: The named reference :1 was invoked but never defined (see the help page).
  4. ^ Trenberth, Kevin E.; Fasullo, John T.; O'Dell, Chris; Wong, Takmeng (2010). "Relationships between tropical sea surface temperature and top‐of‐atmosphere radiation". Geophysical Research Letters. 37 (3). Bibcode:2010GeoRL..37.3702T. doi:10.1029/2009GL042314. ISSN 0094-8276. S2CID 6402800.
  5. ^ Trenberth, Kevin E.; Fasullo, John T.; Abraham, John P. (2011). "Issues in Establishing Climate Sensitivity in Recent Studies". Remote Sensing. 3 (9): 2051–2056. Bibcode:2011RemS....3.2051T. doi:10.3390/rs3092051. ISSN 2072-4292.