COMPREHENSIVE DATASETS

CONCEPT:

Comprehensive datasets will be produced of typical extra-tropical layer cloud systems in different regions. These will act as testbeds for model development and validation as well as for remote sensing studies. The selected cases should represent well-observed, typical situations rather than unusual ones.

CONTENTS:

• Large scale analyses and satellite imagery
• Large scale forcing from NWP
• Detailed surface features
• Raw data from special observational platforms
• Satellite-derived parameter fields (from for example ISCCP)
• High-resolution cloud system model output
• Large scale impacts from high-resolution models

ACCESS:

Appropriate means of accessing and exchanging information will need to be developed.

CASES:

A list of present cases (as described in the LAYER CLOUD SYSTEM CASES section) and expected cases (from upcoming field experiments) is as follows:

oceanic situations:

• snow-producing high latitude warm front
• deepening storm over western Atlantic
• mature systems over eastern Atlantic
• multi-layered occluded system over North Sea

coastal situations:

• 'cool change' over Australia
• frontal system passage into Baltic Sea region
• frontal passage over Southern Japan

continental cases:

• heavy rain over New Zealand (strong orography)
• upslope snowfall over Colorado (strong orogrpahy)
• additional winter systems over North America from GCIP-NC in 1997/98 (weak orogrpahy)

FIRST CASE:

The first case is the Australian 'cool change', coastal case one it has been well-documented and is over flat terrain. The comprehensive dataset has been prepared by Brian Ryan. This case was the main focus of the intercomparison effort at the 1997 WG3 Workshop. Further information is available through the WORKSHOPS section of this home page.

COMMENTS:

The contacts for the different cases are shown in the LAYER CLOUD SYSTEM CASES section. It is envisioned that the comprehensive datasets will largely be maintained by the contacts but be accessible through WWW. CDs will also be produced of the data for wide distribution.