1. Automatic observation of cloudiness: Analysis of all-sky images Yézer González 1 César López 1 Emilio Cuevas 2 1. Sieltec Canarias S.L. 3. Izaña Atmospheric Research Center (AEMET) Spain TECO - 2012 | Brussels (Belgium) | 16-18 October 2012

2. Automatic observation of cloudiness: Analysis of all-sky images Yézer González, César López and Emilio Cuevas TECO-2012 | Brussels | 16-18 October 2012 2 Cloud cover estimation -The influence of clouds on Earth´s radiation balance is a key component of the atmospheric system. -Cloud monitoring is important for aeronautical purposes and weather forecast. These observations are subject to subjective errors. -Cloud cover estimation is an activity traditionally performed by human observations. These observations are subject to subjective errors. -Poor espacial and temporal resolution.

3. Automatic observation of cloudiness: Analysis of all-sky images Yézer González, César López and Emilio Cuevas TECO-2012 | Brussels | 16-18 October 2012 3 SONA Automatic System of Cloud Observation SONA features - CCD sensor. 640x480 pixels, 8 bit, color response from 400 to 700nm and monochrome response from 400 to 1000nm. - Very durable aluminium housing. - Borosilitate dome. - Rotating shadow band. - Cooling/heating system (-10º to +50ºC). - Fast frame rates (up to 70 fps). - Adjustable JPEG compressed still-images or live MJPEG streaming video. - Transfer of images via FTP, RTP or HTTP. - Camera control via HTTP, XML-RPC, Telnet

4. Automatic observation of cloudiness: Analysis of all-sky images Yézer González, César López and Emilio Cuevas TECO-2012 | Brussels | 16-18 October 2012 4 SONA Automatic System of Cloud Observation SONAs in Spain

5. Automatic observation of cloudiness: Analysis of all-sky images Yézer González, César López and Emilio Cuevas TECO-2012 | Brussels | 16-18 October 2012 5 The site -SONA has been developed and tested at the Izaña Atmospheric Observatory (IZO; 28.5ºN 16ºW; 2,400 m a.s.l.) -IZO is a Global Atmospheric Watch (GAW) observatory (www.aemet.izana.org) of global importance with a complete atmospheric components measurement program.

6. Accurate cloud detection and monitoring is a challenge Automatic observation of cloudiness: Analysis of all-sky images Yézer González, César López and Emilio Cuevas TECO-2012 | Brussels | 16-18 October 2012 6 Cloud Detection Procedure

7. Accurate cloud detection and monitoring is a complex problem (A) Biological neuron. (B) Computer neuron model or perceptron. (C) Multilayer neural network with and input layer, two hidden neuron layers and a neuron output layer. Automatic observation of cloudiness: Analysis of all-sky images Yézer González, César López and Emilio Cuevas TECO-2012 | Brussels | 16-18 October 2012 7 Cloud Detection Procedure

8. Calibration and training Automatic observation of cloudiness: Analysis of all-sky images Yézer González, César López and Emilio Cuevas TECO-2012 | Brussels | 16-18 October 2012 8 Cloud Detection Procedure

9. Automatic observation of cloudiness: Analysis of all-sky images Yézer González, César López and Emilio Cuevas TECO-2012 | Brussels | 16-18 October 2012 9 Cloud Detection Procedure Detection

10. Automatic observation of cloudiness: Analysis of all-sky images Yézer González, César López and Emilio Cuevas TECO-2012 | Brussels | 16-18 October 2012 10 Cloud Detection Procedure Image cloud detection in progress…

11. Automatic observation of cloudiness: Analysis of all-sky images Yézer González, César López and Emilio Cuevas TECO-2012 | Brussels | 16-18 October 2012 11 Aerosols and Haze Single photo analysis Multiphoto analysis Saharan dust More uncorrelated inputs

12. Automatic observation of cloudiness: Analysis of all-sky images Yézer González, César López and Emilio Cuevas TECO-2012 | Brussels | 16-18 October 2012 12 Aerosols and Haze Original photo Single analysis Multiphoto analysis

13. Automatic observation of cloudiness: Analysis of all-sky images Yézer González, César López and Emilio Cuevas TECO-2012 | Brussels | 16-18 October 2012 13 Results SONA vs. human observations

14. Cloud Nowcasting Automatic observation of cloudiness: Analysis of all-sky images Yézer González, César López and Emilio Cuevas TECO-2012 | Brussels | 16-18 October 2012 14 Ongoing and Future Activities SONA + photovoltaic system

15. Automatic observation of cloudiness: Analysis of all-sky images Yézer González, César López and Emilio Cuevas TECO-2012 | Brussels | 16-18 October 2012 15 Ongoing and Future Activities Cloud flow determination Implement last developments of High Resolution Winds Products (Atmospheric motion vectors -AMVs- from MSG/HRVIS) achieved by NWC SAF. Goal: perform cloud nowcasting using all sky camera images. J. García-Pereda AEMET

16. Automatic observation of cloudiness: Analysis of all-sky images Yézer González, César López and Emilio Cuevas TECO-2012 | Brussels | 16-18 October 2012 16 Ongoing and Future Activities Cloud Nowcasting. NWC SAF products Cloud Mask Cloud Type Cloud Top HeightCloud Top Pressure

17. Automatic observation of cloudiness: Analysis of all-sky images Yézer González, César López and Emilio Cuevas TECO-2012 | Brussels | 16-18 October 2012 17 Ongoing and Future Activities Cloud base height estimation Goal: Estimate type of clouds and corresponding solar radiation attenuation coefficients Two SONA cameras

18. Automatic observation of cloudiness: Analysis of all-sky images Yézer González, César López and Emilio Cuevas TECO-2012 | Brussels | 16-18 October 2012 18 Acknowledgements -SONA project has received a grant from Consejería de Hacienda, Canary Islands Government, FEDER funds. -CIAI´s Basic System Unit (Ramón Ramos, Rubén del Campo, Cándida Hernández, Virgilio Carreño, Fernando de Ory, Enrique Reyes, Antonio Cruz, Rocío López y Néstor Castro) -NWC SAF information for cloud Nowcasting -Engineers and technicians from SIELTEC

19. Thank You Automatic observation of cloudiness: Analysis of all-sky images Yézer González, César López and Emilio Cuevas TECO-2012 | Brussels | 16-18 October 2012