1 / 14

Good bye!! Cold tropopause

Good bye!! Cold tropopause. ?. 気候物理コアモデル改良サブグループ 渡辺真吾. What ’ s cold bias?. JJA Temperature biases. -10 K. -5 K. UM - ERA40. 5.7b - ERA40. -10 +10. mstrn8. UM. Underestimation of shortwave heating rate?. Shortwave heating rate [K/day] in the tropics (10S-10N) ; Jan. GSM/JMA.

zarek
Download Presentation

Good bye!! Cold tropopause

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. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Good bye!!Cold tropopause ? 気候物理コアモデル改良サブグループ 渡辺真吾

  2. What’s cold bias? • JJA Temperature biases -10 K -5 K UM - ERA40 5.7b - ERA40 -10 +10

  3. mstrn8 UM Underestimation of shortwave heating rate? • Shortwave heating rate [K/day] in the tropics (10S-10N) ; Jan GSM/JMA

  4. New radiation codemstrnX (radX) • Newer release of HITRAN (HIgh-resolution TRANsmission molecular absorption database) HITRAN`92 ⇒HITRAN`00 • Highly optimized integration scheme for K-distribution method

  5. mstrnX mstrn8 UM Improvement in theshortwave heating rate • Shortwave heating rate [K/day] in the tropics (10S-10N) ; Jan GSM/JMA

  6. mstrnX mstrnX_noGWD mstrn8 ERA40 • Temperature profiles in the tropics (10S-10N); January

  7. -10 K noGWD - ERA40 5.7b - ERA40 Meridional structure? • JJA Temperature biases radX - ERA40 -10 +10

  8. radX - ERA40 CH4 oxidation Moist / Dry biases • JJA humidity biases [%difference] 5.7b - ERA40 -100 +100

  9. Summary #.1 • The cold tropopause has been caused by shortcomings of the previous radiation code. • Temperature and humidity biases were significantly reduced. • Some tuning parameters (e.g., GWD) must be re-concerned.

  10. How about lower resolution models? mstrn8 • JJA Temperature biases -10 K -10 K -15 K -5 K T21L40 - ERA40 5.7b - ERA40 -10 +10

  11. mstrnX • JJA Temperature biases -6 K -12 K T21L40 - ERA40 T106L56 - ERA40 -10 +10

  12. Moist / Dry biases mstrnX • JJA humidity biases [%difference] T21L40 - ERA40 T106L56 - ERA40 -100 +100

  13. Cloud water distribution mstrnX • JJA cloud water [kg/kg] T21L40 - ERA40 T106L56 - ERA40 0 5x10-5

  14. Why cold & moist biases are still significant in T21L40? • Lower vertical resolution near the tropopause (dZ=~1.5 km) • Lower horizontal resolution; 5.6 • Insufficient GWD? • Physical processes (all parameters are tuned for T106+full physics)

More Related