Title: Ace-Asia: Kosan (KOS) in-situ measurements of aerosol light scattering and absorption coefficients at 1um and 10 um aerosol size cuts.

 

Contact:

 

John A. Ogren (john.ogren@noaa.gov, phone: (303)497-6210)

Anne Jefferson(anne.jefferson@noaa.gov, phone: (303)497-6493)

NOAA Climate Monitoring and Diagnostics Laboratory (CMDL)

325 Broadway R/CMDL 1

Boulder, CO 80305, USA

Fax: (303)497-5590

Web: http://www.cmdl.noaa.gov/aero/

 

 

Data Set Description:

This README file describes the file format of the a_H01Q2.kos file, which contains data of aerosol light scattering and absorption coefficients taken at the Kosan measurement site on Cheju Island, South Korea from April 5, 2001 to June 26, 2001. Additional files containing aerosol hygroscopic growth data will be added at a later time. The scattering coefficients were measured at three wavelengths (450, 550 and 700 nm) using a TSI model 3563 integrating nephelometer operated at a flow rate of 30 lpm. The absorption coefficient data were collected with a Radiance Research Particle Soot Absorption Photometer at 565 nm radiation and a flow rate of approximately 0.7 lpm. The data have not been adjusted yet to ambient relative humidity and temperature. The relative humidity inside the nephelometer is given in the dataset. Data reported in this file are one hour averages.

Aerodynamic size cuts of the aerosol sample at sub 1um and sub10 um were performed at a relative humidity of 50%.

Nephelometer truncation corrections have been applied to the aerosol scattering coefficients. Corrections to the scattering data for instrument drift between calibrations have not been applied yet. Spot size, flow rate and scattering corrections have been applied to the aerosol absorption coefficient data.

All data files are plain ASCII text, in comma-separated, fixed-length fields. The end of a record is denoted by a linefeed character (ASCII hex 10), which optionally may be preceded by a carriage return.

Universal Coordinated Time (UTC) is used for all time fields. For averaged data, the time reported is the start of the averaging interval.

Leading plus signs are replaced with a blank. This is the common format for the basic measurements obtained at a high time resolution. Missing value codes are always positive. For stations where a particular instrument is not present, the corresponding data field may be either empty or contain the missing value code for that parameter.

A flags field is used in ambient aerosol data files to indicate sampling conditions and data processing status.

 

Field definition

 

Each File Code, Status Code combination has a specific format, as described below:

 

 

File: a_[Ahmd]<timecode>.<STN>[average format]

A negative value in field 44 through 58 corresponds to an arithmetic average for the hourly average and standard deviation. Fields 6-11 refer to the "default" size range, which has either no upper size cut or a 10-um upper size cut (aerodynamic diameter).  Fields 13-19 are for the "alternate" size range, which has a 1-um upper size cut (aerodynamic diameter).
 

Col #

Name

Format and Missing Value Code (mvc)

Description

Scanf info

1

Station_ID

WSA

3-character ID code

%3s

2

Year

1993

Year

%4d

3

StartTime_UTC

123.12

Integer part is Day of Year, 
1 = January 1. Fractional part is time at the start of the averaging interval, UTC. 

%6.2f

4

Flags

0011

4-character code representing system status. 

%4s

5

Bap_G

(default size)

9.999e-99

Aerosol light absorption coefficient (m-1), green channel.

%10.3e

6

Bsp_B

(default size)

9.999e-99

Aerosol total light scattering coefficient (m-1), blue channel.

%10.3e

7

Bsp_G

(default size)

9.999e-99

Aerosol total light scattering coefficient (m-1), green channel.

%10.3e

8

Bsp_R

(default size)

9.999e-99

Aerosol total light scattering coefficient (m-1), red channel.

%10.3e

9

Bbsp_B
-or-
Bsp_NIR

(default size)

9.999e-99

Aerosol backwards-hemispheric light scattering coefficient (m-1), blue channel. For stations equipped with 4-wavelength nephelometers, this field is aerosol total light scattering coefficient (m-1), near infrared channel.

%10.3e

10

Bbsp_G

(default size)

9.999e-99

Aerosol backwards-hemispheric light scattering coefficient (m-1), green channel.

%10.3e

11

Bbsp_R

(default size)

9.999e-99

Aerosol backwards-hemispheric light scattering coefficient (m-1), red channel.

%10.3e

12

Neph_RH

999

Relative Humidity (percent) inside nephelometer

%4d

13

Bap_G,
(alternate size)

9.999e-99

Aerosol light absorption coefficient (m-1), green channel.

%10.3e

14

Bsp_B,
(alternate size)

9.999e-99

Aerosol total light scattering coefficient (m-1), blue channel.

%10.3e

15

Bsp_G,
(alternate size)

9.999e-99

Aerosol total light scattering coefficient (m-1), green channel.

%10.3e

16

Bsp_R,
(alternate size)

9.999e-99

Aerosol total light scattering coefficient (m-1), red channel.

%10.3e

17

Bbsp_B
-or-
Bsp_NIR,
(alternate size)

9.999e-99

Aerosol backwards-hemispheric light scattering coefficient (m-1), blue channel. For stations equipped with 4-wavelength nephelometers, this field is aerosol total light scattering coefficient (m-1), near infrared channel.

%10.3e

18

Bbsp_G,
(alternate size)

9.999e-99

Aerosol backwards-hemispheric light scattering coefficient (m-1), green channel.

%10.3e

19

Bbsp_R,
(alternate size)

9.999e-99

Aerosol backwards-hemispheric light scattering coefficient (m-1), red channel.

%10.3e

20

SD_Bap_G

9.999e-99

Standard deviation of Bap_G data this period

%10.3e

21

SD_Bsp_B

9.999e-99

Standard deviation of Bsp_B data this period

%10.3e

22

SD_Bsp_G

9.999e-99

Standard deviation of Bsp_G data this period

%10.3e

23

SD_Bsp_R

9.999e-99

Standard deviation of Bsp_R data this period

%10.3e

24

SD_Bbsp_B
-or-
SD_Bsp_NIR

9.999e-99

Standard deviation of Bbsp_B or Bsp_NIR data this period

%10.3e

25

SD_Bbsp_G

9.999e-99

Standard deviation of Bbsp_G data this period

%10.3e

26

SD_Bbsp_R

9.999e-99

Standard deviation of Bbsp_R data this period

%10.3e

27

SD_Neph_RH

999

Standard deviation of Neph_RH data this period

%4d

28

SD_CN_ambient,
(alternate size)

9.999e-99

Standard deviation of CN_ambient (alternate size) data this period

%10.3e

29

SD_Bap,
(alternate size)

9.999e-99

Standard deviation of Bap (alternate size) data this period

%10.3e

30

SD_Bsp_B,
(alternate size)

9.999e-99

Standard deviation of Bsp_B (alternate size) data this period

%10.3e

31

SD_Bsp_G,
(alternate size)

9.999e-99

Standard deviation of Bsp_G (alternate size) data this period

%10.3e

32

SD_Bsp_R,
(alternate size)

9.999e-99

Standard deviation of Bsp_R (alternate size) data this period

%10.3e

33

SD_Bbsp_B

9.999e-99

Standard deviation of Bbsp_B or Bsp_NIR (alternate size) data this period

%10.3e

34

SD_Bbsp_G,
(alternate size)

9.999e-99

Standard deviation of Bbsp_G (alternate size) data this period

%10.3e

35

SD_Bbsp_R,
(alternate size)

9.999e-99

Standard deviation of Bbsp_R (alternate size) data this period

%10.3e

36

N_Bap_G

99999

Number of data points used in computation

%6d

37

N_Bsp_B

99999

Number of data points used in computation

%6d

38

N_Bsp_G

99999

Number of data points used in computation

%6d

39

N_Bsp_R

99999

Number of data points used in computation

%6d

40

N_Bbsp_B

99999

Number of data points used in computation

%6d

41

N_Bbsp_G

99999

Number of data points used in computation

%6d

42

N_Bbsp_R

99999

Number of data points used in computation

%6d

43

N_CN_ambient,
(alternate size)

99999

Number of data points used in computation

%6d

44

N_Bap_G,
(alternate size)

99999

Number of data points used in computation

%6d

45

N_Bsp_B,
(alternate size)

99999

Number of data points used in computation

%6d

46

N_Bsp_G,
(alternate size)

99999

Number of data points used in computation

%6d

47

N_Bsp_R,
(alternate size)

99999

Number of data points used in computation

%6d

48

N_Bbsp_B

99999

Number of data points used in computation

%6d

49

N_Bbsp_G,
(alternate size)

99999

Number of data points used in computation

%6d

50

N_Bbsp_R,
(alternate size)

99999

Number of data points used in computation

%6d

 

The default size range is defined to be the total from 0-10 um aerodynamic diameter. The alternate size range is from 0-1 um aerodynamic diameter.