AEROSOL OPTICAL DEPTH INTERCOMPARISON BETWEEN AERONET AUTOMATIC SUNPHOTOMETERS AND HAND HELD SUNPHOT

1
AEROSOL OPTICAL DEPTH INTERCOMPARISON BETWEEN
AERONET AUTOMATIC SUNPHOTOMETERS AND HAND HELD
SUNPHOTOMETERS IN THAILAND

• Boonjawat, J. Eck, T.F. Holben,B.N.
  Schafer,J.S. Reid,J.S. Dubovik,O Smirov,D.
  Lincoln,E.Babbitt,R. Kaewkongka,T.
  Mongkolnavin,R Khantiyanan, W.Mungkaka,K.
  Sinburanapanont,K. Sukanjanaset, W.
  Waitayangoon, Tipjariyaudom,Y Suchareekul,J.
  and Meesiri, S.

2
AERONET

• Aerosol Robotic Network (AERONET)
• Cimel Automatic Sun Photometer
• Solar and Radiance Measurements

3
(No Transcript)
4
Aerosol Optical Depth

• AERONET
• Chiang Mai
• Om Koi
• Bangkok
• Chulalongkorn University
• Nakhon Ratchasima
• Phi mai
• Prachuab Khiri Khan
• Hua Hin
• Mukdahan
• Chulabhorn School

• Handheld Sunphotometer
• Chiang Mai
• Omkoi high/Low
• Bangkok
• 16 schools, IPST, 2xChula
• Nakhon Ratchasima
• Phi mai
• Prachuab Khiri Khan
• Hua Hin

5
Hazemeter Description

• Hand-held Manual Sun photometer
• Stores measurements based on suns light energy
  reaching instrument

6
Hazemeter Description

• Measures from Visible to near-infrared spectrum
  (405, 500, 650, 880nm)
• Uses photodiode filters (10nm bandwidth)

7
Hazemeter Components
8
(No Transcript)
9
Sahel
Brazil
10
Calibration

• Gain adjustments for new filters
• Solar Simulator
• Real-time calibration measurements
• AERONET master in BCL sun mode (measurement every
  minute)
• Calibration analysis
• Transfer calibration from AERONET master
  instrument
• Uses log-log scale of AOT and wavelength

11
Site Information

• GPS Readings
• Latitude
• Longitude
• Elevation
• Importance Calculation of parameters for AOT

12
Measurements

• Triplet Measurement
• 3 single measurements every minute for 3 minutes
• Frequency of Triplet
• Every 30 minutes
• Duration
• At least 6 hours
• Within 3 hours of solar noon

13
Data Submission

• http//aeronet.gsfc.nasa.gov/haze_upload.html
• File Name format
• Current date
• School or location name
• Underscore _
• Only one underscore in file name
• Must appear between school name and instrument
  number
• Instrument Number
• File Name Extension (e.g., .txt)
• Example File Name
• 20022003Bangkoksecondary_88.txt

14
(No Transcript)
15
Data Processing

• AOT profiles created for each site
• Data appears on web site within hours
• http//aeronet.gsfc.nasa.gov/
• Aerosol/Flux Networks
• Hazemeter Network

16
(No Transcript)
17
Chulalongkorn University, Bangkok- Urban
SiteFine mode aerosols dominate r0.15-0.16 um
at Ta4400.7
18
Phi Mai- Biomass Burning Site Related to
Agricultural Practice
19
(No Transcript)
20
(No Transcript)
21
Om Koi Biomass Burning RegionLower altitude
813m, higher AOT than 1120m
22
Om Koi Alt.1120/813m
23
Hua Hin Background Aerosols
24
(No Transcript)
25
Post-Analysis

• Instruments are returned to NASA GSFC
• Post-calibration
• Calibration Analysis
• Data Reprocessing
• Linear interpolation of calibration

26
Summary

• Process Data From Thailand
• Comparisons
• AERONET Sun photometers
• Satellite Validation (e.g., Terra/MODIS)
• Better Understanding of Aerosol Particles in
  Thailand

27
Bangkok and hand held sunphotometer network GLOBE
Project coordinated by IPST SEA START RC
PM 10 Stations Pollution Contol Department
28
Chulalongkorn University and schools around AOT
500nm 0.65-0.75
29
(No Transcript)
30
(No Transcript)
31
Two schools in Nonthaburi Province AOT500nm
0.725-0.768
32
Four schools north of Chulalongkorn University
Main road
Small road
33
Two schools in the west of Chula
34
One school in Samutprakan Province
35
Conclusion for Bangkok

• AOT at 500 nm in BMA about 0.7 during Feb- March
  2003
• AOT at shorter wavelengths are higher than longer
  wavelength
• Data intercomparison at level 1.0 between
  handheld sunphotometers and automatic
  sunphotometer at Chulalongkorn University are
  quite similar
• PM10 data from PCD in Bangkok 1998-2004 exceed
  standard 24 hrs average of 120 microgram/m3 in
  November, December, January and February,
  especially on 25-26 December every year because
  of human activity.

36
Phi Mai Agricultural area casava, sugar cane,
rice