Where should we add some for better forecast?

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Introduction to "ALERA"

ALERA is a new atmospheric objective analysis dataset produced by JAMSTEC.
This is produced by using an ensemble Kalman filter assimilation technique,
so that we get a very "interesting" and "useful" product.


http://www.jamstec.go.jp/esc/afes/alera/

Reference:
"The influence of the observations propagated
by convective coupled equatorial waves"

Qoosaku Moteki1,*, Kunio Yoneyama1, Ryuichi Shirooka1,
Hisayuki Kubota1, Kazuaki Yasunaga1, Junko Suzuki1,
Ayako Seiki1, Naoki Sato2, Takeshi Enomoto3,
Takemasa Miyoshi4, Shozo Yamane5

Article first published online: 18 APR 2011

DOI: 10.1002/qj.779

The Quarterly Journal of the Royal Meteorological Society
Volume 137, Issue 656, pages 641--655, April 2011 Part A

Abstract:
This paper describes the propagation of the influence of radiosonde observations made during MISMO (Mirai Indian Ocean cruise for the Study of the Madden--Julian oscillation-convection Onset), which was conducted over the Indian Ocean in the boreal autumn of 2006. The impact of these observations was assessed using an experimental reanalysis called 'ALERA' that was produced by the local ensemble transform Kalman filter with the atmospheric global circulation model for the Earth Simulator. The difference of the analysis ensemble mean between the analysis cycles with and without the MISMO observations was used to quantify the influence of these observations on the analysis field, which we call impact signals. Since the impact signals were contaminated by noise, probably due to the model's truncated spectral basis, a significance test was performed using the analysis ensemble spread, and the numerical noise was then successfully eliminated. The results indicated that convectively coupled equatorial waves propagated the impact signals to the central Pacific to the east and to the African continent to the west. In particular, the analysis fields around typhoons Cimaron, Chebi, and Durian over the tropical Western Pacific were significantly modified by the propagation of the impact signals through the Kelvin waves. Here two factors played important roles: (1) the meridional positions of the typhoons; and (2) the duration of the observations. The equatorial Rossby waves also made a significant contribution to the propagation of the impact signals. Such influences through the waves resulted in the reduction of the analysis spread. The shape of the region of reduced spread resembled the Matsuno--Gill pattern with an east-west width of more than 20000 km.

Copyright © 2011 Royal Meteorological Society

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Where should we add some for better forecast?

  1. 1. MOTEKI Qoosaku Tropical Climate Variability Research Program Japan Marine-Earth Science and Technology
  2. 2. Where should we add observations in the Tropics? ion projects sive observat Inten y JAMSTEC conducted b
  3. 3. Operational Upper-air Sounding
  4. 4. z z 1-D 2-D t t Weather Station Radio Sonde 3-D y x Weather Radar t
  5. 5. Where should we add observations in the Tropics? ion projects sive observat Inten y JAMSTEC conducted b
  6. 6. CINDY Oct.-Dec. 2011 Radar Vessel
  7. 7. How much improvement do you get? ion projects sive observat Inten y JAMSTEC conducted b
  8. 8. Improvement by CINDY degrade improvement rate (%) = improve % Error without Obs. - Error with Obs. Error without Obs.
  9. 9. observation Spread ≒ Error next analysis forecast current analysis
  10. 10. Objective evaluation of the ”value” of Additional observations
  11. 11. Analysis error of U during MISMO2006 ● operational sounding small error (m/s) large error
  12. 12. Analysis error of U during MISMO2006 ● MISMO sounding ● operational sounding small error (m/s) large error
  13. 13. ALERA available from http://www.jamstec.go.jp/esc/research/ oreda/products/
  14. 14. Improvement by CINDY degrade improvement rate (%) = improve % Error without Obs. - Error with Obs. Error without Obs.
  15. 15. Message
  16. 16. Continuous contribution needs continuous connection
  17. 17. continuous connection on the Youtube
  18. 18. the Youtube leads details
  19. 19. the video like a music
  20. 20. JAMSTEC original products will surely contribute for better forecast in the Tropics

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