Investigating Heatwave Duration Index for Vietnam CSIRO MARINE AND ATMOSPHERIC RESEARCH Trung NGUYEN QUANG (1), Dr. Peter HOFFMANN (2) (1) Hanoi University of Science, VNU, Vietnam (2) CMAR, Aspendale, Australia CMAR Aspendale October - December, 2012

Content  Motivation  Data  Analysis procedure  Results  Conclusion Investigating HWDI for VN | Trung NGUYEN QUANG and Peter HOFFMANN 2 |

Motivation Investigating HWDI for VN | Trung NGUYEN QUANG and Peter HOFFMANN 3 | CCAM How to run? Change options Output Etc… Heat wave in Vietnam Analysis tool Discussion Cherax, burnet CSIRO library

Investigating HWDI for VN | Trung NGUYEN QUANG and Peter HOFFMANN 4 | Motivation HEAT WAVE Hot weather In a row Hanoi 2011 Vinh 2012 HCM 2010

Investigating HWDI for VN | Trung NGUYEN QUANG and Peter HOFFMANN 5 | Motivation  Heat wave duration index (HWDI): maximum period > 5 consecutive days with Tmax >5°C above the 1961–1990 daily Tmax normal [Zhihong Jiang et al. (2012), P. Frich et al. (2002)]  Limitations: Not really valid outside mid-latitude climates  Change: Lw: consecutive days Tmax > Tau °C Above Tmax normal days or 90 th /95 th Percentile

Investigating HWDI for VN | Trung NGUYEN QUANG and Peter HOFFMANN 6 | Data Period: Observation data: 56 stations (from HUS) => Use 51 ( no landmark for 5)  Tx_1980_2003.dat CCAM output: C96_27_106.0_16.0_.07_ERAINT_MUL.YYY MM_sfdata.nc  Tx_CCAM_1980_2003.txt

Investigating HWDI for VN | Trung NGUYEN QUANG and Peter HOFFMANN 7 | Analysis procedure Station data CCAM output Station selection T max HWDI Comparison Using Tx normal Using percentile Lw=5, Tau=5, Upc=.false. Pc=0.95 Aper=.false. run_HWDI.sh Height correction (-0.6/100 m) Validate T max

Investigating HWDI for VN | Trung NGUYEN QUANG and Peter HOFFMANN 8 | Results Mean Error (left), Root Mean Square Error (center) and Correlation Coefficient (right) of daily maximum temperature (Tx) for CCAM output compared with the observations in period Validate maximum temperature (Tx)

Investigating HWDI for VN | Trung NGUYEN QUANG and Peter HOFFMANN 9 | Results Timeseries of monthly maximum temperature (Tx) for CCAM output (blue) and the observations (red) in period Validate maximum temperature (Tx)

Investigating HWDI for VN | Trung NGUYEN QUANG and Peter HOFFMANN 10 | Results HWDI (days) from CCAM output (right) and observation data (left) for period CCAMOBS

Investigating HWDI for VN | Trung NGUYEN QUANG and Peter HOFFMANN 11 | Results OBS Inter-annual of HWDI from CCAM output (bottom) and observations (top) in period CCAM

Investigating HWDI for VN | Trung NGUYEN QUANG and Peter HOFFMANN 12 | Results Slope of the linear trend line of HWDI from CCAM output (right) and observations (left) for period CCAM OBS

Investigating HWDI for VN | Trung NGUYEN QUANG and Peter HOFFMANN 13 | Results CCAMOBS The HWDI (days) using 90 th percentile from CCAM output (right) and observation data (left) for period

Investigating HWDI for VN | Trung NGUYEN QUANG and Peter HOFFMANN 14 | Results CCAMOBS The HWDI (days) using 95 th percentile from CCAM output (right) and observation data (left) for period

Investigating HWDI for VN | Trung NGUYEN QUANG and Peter HOFFMANN 15 | Conclusion  Heat wave in Vietnam can be determined using HWDI except southern part.  R4 is remarkable region for heat wave assessment.  Using percentile approaches should be applied  Continue with changing the threshold or adding new variables (Apparent Temperature, Humidity...)

Thank you for your attention CSIRO MARINE AND ATMOSPHERIC RESEARCH CMAR Aspendale October - December, 2012