Home > News > Seminars > Séminaire de Adrian Tompkins au LMD-Jussieu


Title : Cloud overlap, water vapour distributions in the tropics and subseasonal versus seasonal predictions.
Name of the speaker : Adrian Tompkins
Affiliation :
Laboratory organizer : LMD
Date and time : 25-05-2018 10h30
Location : Campus de Jussieu, salle Darcy (46-56, 3e ét.)
Summary :

The informal talk will cover a number of different areas concerning clouds, convection and tropical predictions:

  • Part 1: will concern the treatment of overlap of clouds in models.  I will first show how the interpretation of overlap commonly used can be systematically biased if clouds are sampled at small spatial scales.  I will then introduce two simple empirical parameterizations that can allow one to consider the impact of the sun angle or wind shear on cloud overlap.
  • Part 2: will consider the distribution of water vapour in the tropics, and using a simple model illustrate the relative impact of various physical processes on the PDF of cloud water.  Using ideas related to recent aggregation work, it will be suggested that water vapour feedbacks to radiation can also impact the tropical PDF.
  • Part3: If time allows I will show a simple back of the envelope analysis that uses the hindcast database of ECMWF, over 6000 hindcasts, to separate the contributions of lead time, model cycle and resolution/set up to the skill advantage of S2S systems over seasonal systems.
Contact :

Si vous souhaitez assister à ce séminaire en visioconférence, merci de contacter marie-pierre.lefebvre@lmd.jussieu.fr