Towards the operational cloud classification in finland
This presentation is the property of its rightful owner.
Sponsored Links
1 / 13

Towards the operational cloud classification in Finland PowerPoint PPT Presentation


  • 95 Views
  • Uploaded on
  • Presentation posted in: General

Towards the operational cloud classification in Finland. Otto Hyvärinen COST 722 Expert Meeting, Helsinki, 9 June 2004. Contents. Cloud classification work with NOAA/AVHRR in FMI in Nowcasting SAF (PPS) Problems Future plans. FMI approach to cloud classification with NOAA/AVHRR.

Download Presentation

Towards the operational cloud classification in Finland

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


Towards the operational cloud classification in finland

Towards the operational cloud classificationin Finland

Otto Hyvärinen

COST 722 Expert Meeting, Helsinki, 9 June 2004


Contents

Contents

  • Cloud classification work with NOAA/AVHRR

    • in FMI

    • in Nowcasting SAF (PPS)

  • Problems

  • Future plans


Fmi approach to cloud classification with noaa avhrr

FMI approach to cloud classification with NOAA/AVHRR

  • The statistical pattern recognition approach

    • Collect a lot of training data

    • Approximate posterior probabilities with neural networks

    • Use a principled way of handling the uncertainty

  • No physics, only data!

    • Different models for day, night and twilight

  • Unfortunately, the development has stalled...


20 september 2001 5 54 utc

20 September 2001, 5:54 UTC


Towards the operational cloud classification in finland

Cloud Classification


Towards the operational cloud classification in finland

Goodness of Cloud/Surface Separation


Nowcasting saf approach with noaa avhrr

Nowcasting SAF approachwith NOAA/AVHRR

  • Developed mostly in SMHI

  • Traditional thresholding

    • Thresholds computed with the help of the radiative transfer models (RTTOV)

  • Uncertainty handled more ad hoc


An example from 8 june 2004 06 20 utc

An example from 8 June 2004, 06:20 UTC

Cloud Mask

Cloud Classification


How do they compare

How do they compare?

  • Comparison against SYNOP observations of total cloudiness

All stations

Stations from "the training area"


Problems

Problems?

  • Common problems

    • Twilight!

    • AVHRR

  • FMI problems

    • no physics  should explore RTMs

  • Nowcasting SAF problems

    • bad decision making methods  should explore pattern recognition methods


Towards future

Towards future

  • Is Nowcasting SAF method for AVHRR "good enough" for us?

  • From AVHRR to MODIS, VIIRS, etc

    • how to make this as least painful as possible?

    • SEVIRI, how useful is it in Finland, really?

  • From the satellite cloud classification to the cloud analysis

    • how to combine remote sensing and in-situ observations with the model data to real 3D analysis of clouds, fog, and visibility?


  • Login