PNG coastal upwelling, ENSO, SPICE, R/V Mirai observation: UPNG presentation Feb2013

585 views

Published on

パプアニューギニア大学における合同ワークショップ講演スライド/2013年2月5日

パプアニューギニア沖沿岸湧昇とエルニーニョおよび
SPICE国際プロジェクト(パプアニューギニア沖係留系観測など)

Published in: Business, Technology
0 Comments
0 Likes
Statistics
Notes
  • Be the first to comment

  • Be the first to like this

No Downloads
Views
Total views
585
On SlideShare
0
From Embeds
0
Number of Embeds
4
Actions
Shares
0
Downloads
0
Comments
0
Likes
0
Embeds 0
No embeds

No notes for slide

PNG coastal upwelling, ENSO, SPICE, R/V Mirai observation: UPNG presentation Feb2013

  1. 1. Takuya HASEGAWA (JAMSTEC-RIGC, Yokosuka, Japan) Physical oceanography Climate system (El Nino/Southern Oscillation: ENSO) Air-sea interactions in the tropical Pacific Oceanic and atmospheric variability around PNG and on-going observations off the New Ireland Island using R/V Mirai PNG, 5th Feb 2013
  2. 2. General background Pacific warm water pool # Pacific warm water pool around PNG (Very high sea surface temperature!) There are many atmospheric and oceanic phenomena on multi-timescale e.g., # tropical cyclone (weekly scale), # Madden-Jullian Oscillation (intraseason-scale variation), # monsoon (seasonal cycle) # El Nino-related interannual-scale variations # decadal-scale change….. --> Impacts on local, and also global (by teleconnections) weather & climate # sea temperature, salinity, sea level, currents, winds, rainfall, etc. Japan Papua New Guinea
  3. 3. 1. Coastal upwelling along New Guinea north coast 2. On-going and near-future oceanic observations around New Ireland Island using R/V Mirai OUTLINE 1. Coastal upwelling 2. New Ireland Island Warm water pool
  4. 4. -Background-:Coastal upwelling along Papua New Guinea Coastal upwelling along Papua New Guinea (New Guinea)     →Generating relatively cool SST Western equatorial Pacifc Existence of New Guinea coastal upwelling (e.g., Lukas1988; Ueki et al. 2003) Purpose of the present study: # To check existence of New Guinea coastal upwelling before onset of El Nino # To explore a mechanism of SST cooling related to New Guinea coastal upwelling New Guin ea Pacific warm pool Westerly wind Bismarck Sea 1. Coastal upwelling 1. Coastal upwelling along New Guinea north coast TRIOTN buoy CTD
  5. 5. Background for coastal upwelling along north coast of New Guinea Existence of coastal upwelling along New Guinea (e.g., Lukas1988; Ueki et al. 2003) New Guinea Island Eastward shift of warm pool Westerly wind Bismarck Sea Expected process (hypothesis) starting strong coastal upwelling along PNG: Occurrence of anomalously strong coastal upwelling → Generates relatively cool sea surface temperature (SST) → Generates positive SST gradient in the warm pool region → Can contributes to enhancement of westerly wind (e.g., Lindzen and Nigram 1987; Eisenman et al. 2005; Gebbie et al. 2007) → Can trogger astward moving of warm pool and resultant El Nino onset (e.g., McPhaden 2004) Onset of El Nino
  6. 6. Purpose of the present study: # To check existence of coastal upwelling in the Bismarck Sea before onset of El Nino # To explore a mechanism of SST cooling related to New Guinea coastal upwelling # To check a relationship between SST cooling and westerly wind
  7. 7. Obs: Upper ocean temperature structure observed by R/V Kaiyo 2.7˚S EQ CTD stations 28 degC Coastal upwelling with relatively cool SST along north coast prior to onset of 2002/03 El Nino Shallower near the coast Latitude-depth diagram of CTD-observed temperature 80m depth 20m depth CTD-observation of the R/V Kaiyo for 21-23 December 2001 (Prior to onset of 2002/03 El Nino) Snapshot of daily SST on 22 December 2001 Shows coastal upwelling Cool sea surface temperatures( SSTs) distribute along coast Hasegawa et al. 2009 JO Depth(m) Latitude (deg) TMI-satellite SST (22 Dec. 2001)
  8. 8. SST from TMI satellite 20 Dec 2001  10 Jan 2002  30 Dec 2001  Relatively cool SST area: Northeastward extension from the coast toward the equator (degC) Obs: Extension of the cold SST area from the coast found in TMI-SST Hasegawa et al. 2009 JO
  9. 9. Heat budget analysis using TRITON buoy Using four TRITON moored buoy at EQ-147E near PNG # Buoy data ->MLT, horizontal heat adv., net surface heat flux # Residual: Vertical heat adv., entrainment cooling, diffusion # Daily data; tide-killer & 7-day running mean filteredDec 2001 Mixed Layer Temp. PNG coastal upwelling period Large contribution of eastward zonal heat advection to cooling, as compared to the net surface heat flux and other factors Effect from zonal heat adv. (degC) R y T v x T u hc Q t T p surface + ∂ ∂ − ∂ ∂ −= ∂ ∂ 0ρ TRITON buoy (EQ-147E) Temporal integration of each term of heat budget equation Mixed Layer Temp. (degC) Hasegawa et al. 2009 JO
  10. 10. Numerical simulation: high-resolution Ocean General Circulation Model (OGCM) hindcast using a super computer “Earth Simulator” of JAMSTEC-ESC Complicated surface currents: related to the coastal upwelling and extension of the cool SST area Hasegawa et al. 2010 (OD) Hasegawa et al. 2011 (JPO) Modeled surface currents averaged 20 Dec2001 – 20 Jan 2002 (upwelling period)
  11. 11. Positive zonal difference in SST (Positive zonal gradient of SST) Westerlywind Large positive zonal gradient of SST accompanies strong westerly wind, which can trigger the El Nino onset via eastward movement of warm water pool   Positive SST zonal gradient →Negative SLP zonal gradient →Enhancement of westerly surface wind (e.g., Kessler & Kleeman 2000) Zonalsurfacewindaveragedover westernequatorialPacific(m/s:140-160E) Warm Zonal difference in SST in the western EQ Pacific (degC) (150-160E minus 140-150E) Cool Westerly Relationship between SST cooling and westerly surface wind (TMI-SST & QuikSCAT surface wind) Hasegawa et al. 2009 JO
  12. 12. onset of El Nino Summary and discussion for coastal upwelling along New Guinea eastward shift of warm pool zonal heat advectionSST cooling Observational and model experiments suggest potential impact of small-scale oceanic variation such as coastal upwelling on large scale climate variations New Guinea positive zonal gradient of SST & strong westerly surface wind Suggestion; Potential impact of small-scale oceanic variations on large-scale climate variations such as El Nino. Also, may be related to fishery, coastal environment, rainfall in PNG
  13. 13. -Background-:Coastal upwelling along Papua New Guinea Coastal upwelling along Papua New Guinea (New Guinea)     →Generating relatively cool SST Western equatorial Pacifc Existence of New Guinea coastal upwelling (e.g., Lukas1988; Ueki et al. 2003) Purpose of the present study: # To check existence of New Guinea coastal upwelling before onset of El Nino # To explore a mechanism of SST cooling related to New Guinea coastal upwelling New Guin ea Pacific warm pool Westerly wind Bismarck Sea 2. On-going and near-future observation around New Ireland Island using R/V Mirai 2. New Ireland Island
  14. 14. To explore western boundary currents around New Guinea and its impact on warm pool changes French  &  USA  subsurface  ADCP  moorings JAMSTEC  subsurface  ADCP  moorings TRITON  buoys _ New  Guinea Subsurface  ADCP  moorings  by  Japan,  USA,  and  France:     To  explore  ouIlows  from  Solomon  Sea  to  Bismarck  Sea  and  western  Pacific      JAMSTEC  moorings:  focus  on  New  Ireland  Coastal  Undercurrent  (NICU),   observing  current  velocity    of  NICU  by  the  moorings     Plus:    various  observaQons  for  oceanic  temperature  and  salinity   Total  target  of  CLIVAR-­‐SPICE   [Sv] Target: Bismarck  Sea   Solomon  Sea   CooperaQon  with  moorings  by  France  and  USA,   based  on  CLIVAR-­‐SPICE  internaQonal  project   (MoorSPICE)  
  15. 15.  Recent  observaQon  by  R/V  Mirai   (MR12-­‐03  cruise  for  Jul-­‐Aug  2012)  
  16. 16. Recent  R/V  Mirai  cruise  (MR12-­‐03  cruise) MR12-­‐03:  During  July-­‐August  2012:        #  Deployment  of  two  ADCPs          (AcousQc  Doppler  Current  Profilers)          subsurface  moorings        #  CTD/Lowered  ADCP  (LADCP)  observaQon            near  mooring  points          (Temp  &  Salinity  profile/current  velocity  profile)        #  Launch  of  one  Argo  float  (Temp  &  salinity  profile)        #  Along  track  conQnuous  observaQons:            XCTD  (Temp  &  salinity  profile)            Shipboard  ADCP  (SADCP:  current  velocity),  etc.      
  17. 17. Design  of  the  JAMSTEC  subsurface  ADCP  moorings     Sea surface CTD sensor (605-685m depth) Anchor Releaser (double) ~3500 m depth Upward ADCP sensor (600-680m depth) Top float (260-400m depth) with upward ADCP (current velocity) & CTD (temperature and salinity) sensors ~ ~ Current velocity observed by ADCP (50m~650m) NICU Two  moorings   for  NICU Sea bottom NICU Deployment of the mooring during MR12-03 cruise
  18. 18. Deployment of the subsurface ADCP mooring from R/V Mirai
  19. 19. Other observations related to ADCP mooring: Argo float, etc. # Argo float is one kind of unmanned drifter, to observe automatically temperature and salinity from roughly 2000m to surface. # One Argo float was launched very near ADCP-mooring point during MR12-03 cruise. NEMO-type float launched during MR12-03 cruise CTD: Temperature, salinity and Pressure sensor
  20. 20.  Plan  for  next  observaQon  by  R/V  Mirai   (MR14-­‐02  cruise  for  Feb-­‐March  2014)  
  21. 21. MR14-­‐02:  During  February-­‐March  2014:        #  Recovery  of  the  two  ADCP  subsurface  moorings        #  CTD/LADCP  observaQon  near  mooring  points            (Temp  &  salinity  profile/current  velocity  profile)        #  Along  track  conQnuous  observaQons:              XCTD  and/or  CTD  (Temp  &  salinity  profile)              SADCP  (current  velocity),  etc.            (if  possible,  launch  of  one  Argo  float  (Temp  &  salinity  profile)  )     Present  rough  plan  for  next  R/V  Mirai  cruise  (MR14-­‐02  cruise)    *  Details  would  be  changed 130˚E 130˚E 140˚E 140˚E 150˚E 150˚E 160˚E 160˚E 170˚E 170˚E 10˚S 10 0˚ 0˚ 10˚N 10 20˚N 20 30˚N 30 40˚N 40 130˚E 130˚E 140˚E 140˚E 150˚E 150˚E 160˚E 160˚E 170˚E 170˚E 10˚S 10 0˚ 0˚ 10˚N 10 20˚N 20 30˚N 30 40˚N 40 130˚E 130˚E 140˚E 140˚E 150˚E 150˚E 160˚E 160˚E 170˚E 170˚E 10˚S 10 0˚ 0˚ 10˚N 10 20˚N 20 30˚N 30 40˚N 40 Sekinehama Hachinohe Koror
  22. 22. R/V Mirai MR12-03 Cruise (Jul-Aug 2013): Two subsurface ADCP moorings were deployed off New Ireland Island, to observe mainly current velocity from 50m to 650m. (Cooperation with CLIVAR-SPICE mooring project: MoorSPICE) In addition, Argo floats was launched near mooring point. Along cruise track, temperature and salinity were observed by XCTD (0-1000m), and current velocity were observed by SADCP and LADCP. Now, we are going to the next cruise observation of R/V Mirai (MR14-02 cruise: Feb-March 2014) These observations will contribute to deeper understanding of mechanism of warm water supply to warm pool through NICU, which can be related to weather and climate changes in PNG and other many countries. Summary for R/V Mirai observations
  23. 23. My published papers for coastal upwelling study: Hasegawa, T., K. Ando, K. Mizuno, and R. Lukas (2009): “Coastal upwelling along north coast of Papua New Guinea and SST cooling over Pacific warm pool: A case study of 2002/03 El Nino”, Journal of Oceanography, vol. 65, 817-833. Hasegawa, T., K. Ando, K. Mizuno, R. Lukas, B. Taguchi, and H. Sasaki (2010): “Coastal upwelling along the north coast of Papua New Guinea and El Nino events during 1981-2005”, Ocean Dynamics, vol. 60, 1255-1269. Hasegawa, T., K. Ando, and H. Sasaki (2011): “Cold water flow and upper-ocean currents in the Bismarck Sea from December 2001 to January 2002”, Journal of Physical Oceanography, vol. 41, 827-834.

×