TITLE: Aerosol light scattering measurements as a function of relative humidity
onboard the Ron Brown Version 1.0
AUTHORS:
Christian M. Carrico
Department of Atmospheric Science
Colorado State University
Ft. Collins, CO 80523
Tel: 970-491-8667
Fax: 970-491-8483
Email: carrico@lamar.colostate.edu
Pinar Kus
Department of Civil and Environmental Engineering, MC-250
University of Illinois at Urbana-Champaign
Urbana, IL 61801
Tel: 217-333-8692
Fax: 217-333-6968
Email: pinarkus@students.uiuc.edu
Mark J. Rood
Department of Civil and Environmental Engineering, MC-250
University of Illinois at Urbana-Champaign
Urbana, IL 61801
Tel: 217-333-6963
Fax: 217-333-6968
Email: m-rood@uiuc.edu
1.0 DATA SET OVERVIEW
The dataset are measurements of aerosol light scattering and backscattering as a
function of relative humidity (RH) for RH between ~40 and 85%. The measurements
occurred onboard the R/V Ronald Brown from 17 March 2001 through 20 April 2001.
The light scattering measurements are at wavelengths of 450, 550, and 700 nm and
alternating between upper particle size cuts of 10 and 1 micrometers. Unless
otherwise specified the parameters given here are for standard temperature and
pressure conditions of 273K and 1013 mbar.
2.0 INSTRUMENT DESCRIPTION
Measurements were made with a controlled relative humidity nephelometry system
(humidograph) [Carrico et al., 1998; 2000]. Aerosol was sampled from the Ron
Brown community aerosol inlet at a height of approximately 20m above sea level
and from which instruments in both aerosol vans on the forward deck sampled.
The community aerosol inlet was conditioned by heating to ~50% RH to allow size
cuts to be imposed at a common RH before sampling by individual instruments.
The humidograph includes two TSI 3563 nephelometers with a humidity control
system located between the instruments. The first nephelometer, the dry
reference nephelometer, is operated at low RH (RH=19 ? 5%) continuously. This
was accomplished by additional sample heating to 33.5 ? 1.9?C). An RH control
system follows the first nephelometer and scans sample RH by adding water vapor
and/or changing temperature. Downstream of the RH controller, the scanning RH
nephelometer measures light scattering properties while scanning RH from ~40% to
85%. RH scans are performed with both increasing controlled RH starting from a
"dry" state and decreasing RH conditions starting from a hydrated state. A
complete increasing and decreasing RH scan (humidogram) is measured in
approximately 45 minutes.
3.0 DATA COLLECTION AND PROCESSING
Nephelometer calibration occurred approximately every 3 days with CO2 and
filtered air. RH and temperature measurements were inter-calibrated before and
during the experiment. Measurements with laboratory generated NaCl and
(NH4)2SO4 were used during the experiment for validation of instrument
operation. Lamp power was decreased and ventilation was increased to diminish
the effects of instrumental heating on the measurements.
Light scattering and backscattering coefficients as a function of controlled RH
are given as f(RH) values for discrete RH values of 35%, 45%, 50%, 60%, 65%,
70%, 75%, 80%, 82%, and 85% . As defined here, f(RH) is the ratio of the
measured light scattering coefficient at the indicated controlled RH to the
light scattering coefficient at the RH of the dry reference nephelometer (also
given in the data file and with average of RH = 19 ? 5%). Based on observed
curve structure, measured f(RH) were fit to one of two curves, monotonic or
deliquescent as given in the table below [Kotchenruther et al., 1999].
Monotonic curves featured smoothly increasing and decreasing f(RH) that
demonstrated similar pathways for increasing and decreasing controlled RH.
Deliquescent curves featured step change(s) in f(RH) and demonstrated a
hysteresis effect with separate f(RH) pathways for increasing and decreasing
controlled RH. Deliquescent step changes are plotted versus RH measured
immediately upstream of the scanning RH nephelometer. This is the point where
the highest RH is achieved within the humidograph (due to nephelometer heating)
and where deliquescence occurs. Curve fit parameters a, b, c, d, and g are
given as appropriate for the curve fit for each humidogram.
Growth Type
Equation
Monotonic
(increasing and
decreasing RH)
Deliquescent
(Increasing
RH)
Deliquescent
(decreasing
RH)
4.0 DATA FORMAT
The data file is a column-separated data file that is comma delimited and time
stamped at the beginning of each nominal 45 minute period. Unless otherwise
noted, the parameters given are for standard temperature and pressure (1013 mbar
and 273K). Meteorological parameters (columns 4 through 20) are courtesy of
Jim Johnson of NOAA-PMEL and are provided for calculation of the parameters at
ambient pressure, temperature, and RH. PMEL light scattering measurements (at
RH~50%) are provided for comparative purposes and are courtesy of Trish Quinn
and Tim Bates. The final 18 columns give low RH reference light scattering and
backscattering coefficient mean values and standard deviations, at ambient
temperature and pressure followed by f(RH=ambient). Thus multiplying
corresponding low RH ambient scattering with f(RH=ambient) values gives
scattering at ambient temperature, pressure, and RH.
Parameter names that end with "UP" apply to increasing controlled RH starting
from "dry" conditions while those including "DN" apply to decreasing controlled
RH starting from a hydrated state. Curve fits that are designated "MON" in the
"Growth_Type" column 25 exhibit the same hygroscopic growth behavior for
increasing and decreasing controlled RH and thus only one curve fit is given.
Curve fits that are designated "DEL" in the "Growth_Type" column 25 exhibit
different pathways for increasing and decreasing controlled RH and have distinct
curve fits given for increasing RH (UP) and decreasing controlled RH (DN).
Each row of the data file gives the following information in the column numbers given
below:
1. filename (YMMDDHHfracH) Time stamp UTC filename (for internal bookkeeping)
2. Date_Time_fRHfile (YYYYMMDDHHMM) UTC date and time for the beginning of f(RH)
measurement. The complete up/down RH scan lasts approximately 45 minutes.
3. DayOfYear_fRHfile (Decimal Day) Day of year for f(RH) measurement based on 1 Feb 12:00
noon UTC = 32.5
4. Date_Time_MET: (YYYYMMDDHHMM) UTC date and time for the meteorological data
5. DayOfYear_MET (Decimal Day) Day of year for meteorological data based on 1 Feb 12:00 noon
UTC = 32.5
6. LAT (Deg) Ship's latitude position in degrees from û90 to +90 degrees
7. LONGT (Deg) Ship's longitude position in degrees from 0 to 360 degrees
8. GPS-course (Deg) Ship's course from 0 to 360 degrees (0=north)
9. GPS-spd (knts) Ship's speed in knots
10. AirT_Ambient (Deg C) ambient air temperature in degrees Celcius
11. RH_Ambient (%) ambient relative humidity in percent
12. Baro (mb) (ambient ?) barometric pressure in millibar
13. Insolation (w m^2) solar flux in watts per square meter
14. WS_rel (m/s) wind speed relative to ship in meters per second
15. WD_rel to bow (deg) wind direction relative to ship direction (-90 port, 0 dead ahead, +90
starboard)
16. WindS (m/s) wind speed relative to ocean surface in meters per second
17. WindD (deg) wind direction relative to ocean surface
18. WindU (m/s) wind to east in meters per second
19. WindV (m/s) wind to north in meters per second
20. RainRate (mm hr-1) rainfall rate in millimeters per hour
21. Size (um) Upper size cut of the measurement (1 or 10 micrometers)
22. PMEL_RH (%) for NOAA-PMEL nephelometer recorded simultaneously
23. PMEL_sp550 (1/Mm) light scattering coefficient in inverse megameters (1/Mm =1e-6/m) at 550
nm for NOAA-PMEL nephelometer for given size cut at T=0¦ C, RH=PMEL_RH, and P=1013
mb.
24. PMEL_Position Determination of whether light scattering measured at RH~50% is on the upper
branch of the hysteresis loop (U), lower branch (L), intermediate (75-closer to upper branch, 50
in the middle, 25 closer to the lower branch), on both the upper and lower curves for the case of
monotonic growth (B), or an is outlier (O) from the f(RH) curve. This position is used to
calculate the ambient f(RH) below.
25. Growth_Type: Curve fit used to measured experimental data. Deliquescent curves (DEL) have
step change(s) in light scattering coefficients at deliquescence and crystallization RH values
with evidence of hysteresis comparing increasing and decreasing RH scans. Monotonic curves
(MON) have smoothly changing light scattering coefficients with little difference between
increasing and decreasing RH scans.
26. DRH (%) Deliquescence RH if the curve fit is deliquescent
27. CRH (%) Crystallization RH if the curve fit is deliquescent. Note that if the value -99 for a
deliquescent type of growth, CRH value could not be determined.
28. RH_ReferenceNeph (%): RH in the low RH reference nephelometer
29. period (min): Duration over which dry scattering values are reported
30. drysp_450_STP (1/Mm) Low RH light scattering coefficient in inverse megameters (1/Mm =1e-
6/m) at 450 nm (at 0¦ C and 1013 mb)
31. devdrysp_450_STP (1/Mm) Standard deviation of drysp_450_STP
32. drysp_550_STP (1/Mm) Low RH light scattering coefficient at 550 nm
33. devdrysp_550_STP (1/Mm) ) Standard deviation of drysp_550_STP
34. drysp_700_STP (1/Mm) Low RH light scattering coefficient at 700 nm
35. devdrysp_700_STP (1/Mm) Standard deviation of drysp_700_STP
36. drybsp_450_STP (1/Mm) Low RH light back scattering coefficient at 450 nm
37. devdrybsp_450_STP (1/Mm) Standard deviation of drybsp_450_STP
38. drybsp_550_STP (1/Mm) Low RH light back scattering coefficient at 550 nm
39. devdrybsp_550_STP (1/Mm) Standard deviation of drybsp_550_STP
40. drybsp_700_STP (1/Mm) Low RH light back scattering coefficient at 700 nm
41. devdrybsp_700_STP (1/Mm) Standard deviation of drybsp_700_STP
42. a_450sp_UP: Parameter a for curve fit for total scattering at 450 nm
43. b_450sp_UP: Parameter b for curve fit for total scattering at 450 nm
44. d_450sp_UP: Parameter d for curve fit for total scattering at 450 nm
45. c_450sp_UP: Parameter c for curve fit for total scattering at 450 nm
46. g_450sp_UP: Parameter g for curve fit for total scattering at 450 nm
47. RMSE_450sp_UP: Fit root mean square errora for f(RH) at 450 nm
48. Conf90_450sp_UP: Confidence widthb in value of f(RH=90%) for total scattering at 450 nm
49. a_550sp_UP: Parameter a for curve fit for total scattering at 550 nm
50. b_550sp_UP: Parameter b for curve fit for total scattering at 550 nm
51. d_550sp_UP: Parameter d for curve fit for total scattering at 550 nm
52. c_550sp_UP: Parameter c for curve fit for total scattering at 550 nm
53. g_550sp_UP: Parameter g for curve fit for total scattering at 550 nm
54. RMSE_550sp_UP: Fit root mean square error of f (RH) fit for total scattering at 550 nm
55. Conf90_550sp_UP: Confidence width in value of f(RH=90%) for total scattering at 550 nm
56. a_700sp_UP: Parameter a for curve fit for total scattering at 700 nm
57. b_700sp_UP: Parameter b for curve fit for total scattering at 700 nm
58. d_700sp_UP: Parameter d for curve fit for total scattering at 700 nm
59. c_700sp_UP: Parameter c for curve fit for total scattering at 700 nm
60. g_700sp_UP: Parameter g for curve fit for total scattering at 700 nm
61. RMSE_700sp_UP: Fit root mean square error of f(RH) fit for total scattering at 700nm
62. Conf90_700sp_UP: Confidence width in value of f(RH=90%) for total scattering at 700nm
63. a_450bsp_UP: Parameter a for curve fit for back scattering at 450 nm
64. b_450bsp_UP: Parameter b for curve fit for back scattering at 450 nm
65. d_450bsp_UP: Parameter d for curve fit for back scattering at 450 nm
66. c_450bsp_UP: Parameter c for curve fit for back scattering at 450 nm
67. g_450bsp_UP: Parameter g for curve fit for back scattering at 450 nm
68. RMSE_450bsp_UP: Fit root mean square error of f (RH) fit for back scattering at 450 nm
69. Conf90_450bsp_UP: Confidence width in value of f(RH=90%) for back scattering at 450 nm
70. a_550bsp_UP: Parameter a for curve fit for back scattering at 550 nm
71. b_550bsp_UP: Parameter b for curve fit for back scattering at 550 nm
72. d_550bsp_UP: Parameter d for curve fit for back scattering at 550 nm
73. c_550bsp_UP: Parameter c for curve fit for back scattering at 550 nm
74. g_550bsp_UP: Parameter g for curve fit for back scattering at 550 nm
75. RMSE_550bsp_UP: Fit root mean square error of f (RH) fit for back scattering at 550 nm
76. Conf90_550bsp_UP: Confidence in value of f(RH=90%) for back scattering at 550 nm
77. a_700bsp_UP: Parameter a for curve fit for back scattering at 700 nm
78. b_700bsp_UP: Parameter b for curve fit for back scattering at 700 nm
79. d_700bsp_UP: Parameter d for curve fit for back scattering at 700 nm
80. c_700bsp_UP: Parameter c for curve fit for back scattering at 700 nm
81. g_700bsp_UP: Parameter g for curve fit for back scattering at 700 nm
82. RMSE_700bsp_UP: Fit root mean square error of f (RH) fit for back scattering at 700 nm
83. Conf90_700bsp_UP: Confidence width in value of f (RH=90%)
84. UPfitfRH_450sp_35: f (RH=35%) value for total scattering at 450 nm
85. UPfitfRH_450sp_45: f (RH=45%) value for total scattering at 450 nm
86. UPfitfRH_450sp_50: f (RH=50 %) value for total scattering at 450 nm
87. UPfitfRH_450sp_60: f (RH=60%) value for total scattering at 450 nm
88. UPfitfRH_450sp_65: f (RH=65%) value for total scattering at 450 nm
89. UPfitfRH_450sp_70: f (RH=70%) value for total scattering at 450 nm
90. UPfitfRH_450sp_75: f (RH=75%) value for total scattering at 450 nm
91. UPfitfRH_450sp_80: f (RH=80%) value for total scattering at 450 nm
92. UPfitfRH_450sp_82: f (RH=82%) value for total scattering at 450 nm
93. UPfitfRH_450sp_85: f (RH=85%) value for total scattering at 450 nm
94. UPfitfRH_550sp_35: f (RH=35%) value for total scattering at 550 nm
95. UPfitfRH_550sp_45: f (RH=45%) value for total scattering at 550 nm
96. UPfitfRH_550sp_50: f (RH=50%) value for total scattering at 550 nm
97. UPfitfRH_550sp_60: f (RH=60%) value for total scattering at 550 nm
98. UPfitfRH_550sp_65: f (RH=65%) value for total scattering at 550 nm
99. UPfitfRH_550sp_70: f (RH=70%) value for total scattering at 550 nm
100. UPfitfRH_550sp_75: f (RH=75%) value for total scattering at 550 nm
101. UPfitfRH_550sp_80: f (RH=80%) value for total scattering at 550 nm
102. UPfitfRH_550sp_82: f (RH=82%) value for total scattering at 550 nm
103. UPfitfRH_550sp_85: f (RH=85%) value for total scattering at 550 nm
104. UPfitfRH_700sp_35: f (RH=35%) value for total scattering at 700 nm
105. UPfitfRH_700sp_45: f (RH=45%) value for total scattering at 700 nm
106. UPfitfRH_700sp_50: f (RH=50%) value for total scattering at 700 nm
107. UPfitfRH_700sp_60: f (RH=60%) value for total scattering at 700 nm
108. UPfitfRH_700sp_65: f (RH=65%) value for total scattering at 700 nm
109. UPfitfRH_700sp_70: f (RH=70%) value for total scattering at 700 nm
110. UPfitfRH_700sp_75: f (RH=75%) value for total scattering at 700 nm
111. UPfitfRH_700sp_80: f (RH=80%) value for total scattering at 700 nm
112. UPfitfRH_700sp_82: f (RH=82%) value for total scattering at 700 nm
113. UPfitfRH_700sp_85: f (RH=85%) value for total scattering at 700 nm
114. UPfitfRH_450bsp_35: f (RH=35%) value for back scattering at 450 nm
115. UPfitfRH_450bsp_45: f (RH=45%) value for back scattering at 450 nm
116. UPfitfRH_450bsp_50: f (RH=50%) value for back scattering at 450 nm
117. UPfitfRH_450bsp_60: f (RH=60%) value for back scattering at 450 nm
118. UPfitfRH_450bsp_65: f (RH=65%) value for back scattering at 450 nm
119. UPfitfRH_450bsp_70: f (RH=70%) value for back scattering at 450 nm
120. UPfitfRH_450bsp_75: f (RH=75%) value for back scattering at 450 nm
121. UPfitfRH_450bsp_80: f (RH=80%) value for back scattering at 450 nm
122. UPfitfRH_450bsp_82: f (RH=82%) value for back scattering at 450 nm
123. UPfitfRH_450bsp_85: f (RH=85%) value for back scattering at 450 nm
124. UPfitfRH_550bsp_35: f (RH=35%) value for back scattering at 550 nm
125. UPfitfRH_550bsp_45: f (RH=45%) value for back scattering at 550 nm
126. UPfitfRH_550bsp_50: f (RH=50%) value for back scattering at 550 nm
127. UPfitfRH_550bsp_60: f (RH=60%) value for back scattering at 550 nm
128. UPfitfRH_550bsp_65: f (RH=65%) value for back scattering at 550 nm
129. UPfitfRH_550bsp_70: f (RH=70%) value for back scattering at 550 nm
130. UPfitfRH_550bsp_75: f (RH=75%) value for back scattering at 550 nm
131. UPfitfRH_550bsp_80: f (RH=80%) value for back scattering at 550 nm
132. UPfitfRH_550bsp_82: f (RH=82%) value for back scattering at 550 nm
133. UPfitfRH_550bsp_85: f (RH=85%) value for back scattering at 550 nm
134. UPfitfRH_700bsp_35: f (RH=35%) value for back scattering at 700 nm
135. UPfitfRH_700bsp_45: f (RH=45%) value for back scattering at 700 nm
136. UPfitfRH_700bsp_50: f (RH=50%) value for back scattering at 700 nm
137. UPfitfRH_700bsp_60: f (RH=60%) value for back scattering at 700 nm
138. UPfitfRH_700bsp_65: f (RH=65%) value for back scattering at 700 nm
139. UPfitfRH_700bsp_70: f (RH=70%) value for back scattering at 700 nm
140. UPfitfRH_700bsp_75: f (RH=75%) value for back scattering at 700 nm
141. UPfitfRH_700bsp_80: f (RH=80%) value for back scattering at 700 nm
142. UPfitfRH_700bsp_82: f (RH=82%) value for back scattering at 700 nm
143. UPfitfRH_700bsp_85: f (RH=85%) value for back scattering at 700 nm
144. c_450sp_DN: Parameter c for curve fit for total scattering at 450 nm
145. g_450sp_DN: Parameter g for curve fit for total scattering at 450 nm
146. RMSE_450sp_DN: Fit root mean square errora for f(RH) at 450 nm
147. Conf90_450sp_DN: Confidence widthb in value of f(RH=90%) for total scattering at 450 nm
148. c_550sp_DN: Parameter c for curve fit for total scattering at 550 nm
149. g_550sp_DN: Parameter g for curve fit for total scattering at 550 nm
150. RMSE_550sp_DN: Fit root mean square error of f (RH) fit for total scattering at 550 nm
151. Conf90_550sp_DN: Confidence width in value of f(RH=90%) for total scattering at 550 nm
152. c_700sp_DN: Parameter c for curve fit for total scattering at 700 nm
153. g_700sp_DN: Parameter g for curve fit for total scattering at 700 nm
154. RMSE_700sp_DN: Fit root mean square error of f(RH) fit for total scattering at 700nm
155. Conf90_700sp_DN: Confidence width in value of f(RH=90%) for total scattering at 700nm
156. c_450bsp_DN: Parameter c for curve fit for back scattering at 450 nm
157. g_450bsp_DN: Parameter g for curve fit for back scattering at 450 nm
158. RMSE_450bsp_DN: Fit root mean square error of f (RH) fit for back scattering at 450 nm
159. Conf90_450bsp_DN: Confidence width in value of f(RH=90%) for back scattering at 450 nm
160. c_550bsp_DN: Parameter c for curve fit for back scattering at 550 nm
161. g_550bsp_DN: Parameter g for curve fit for back scattering at 550 nm
162. RMSE_550bsp_DN: Fit root mean square error of f (RH) fit for back scattering at 550 nm
163. Conf90_550bsp_DN: Confidence in value of f(RH=90%) for back scattering at 550 nm
164. c_700bsp_DN: Parameter c for curve fit for back scattering at 700 nm
165. g_700bsp_DN: Parameter g for curve fit for back scattering at 700 nm
166. RMSE_700bsp_DN: Fit root mean square error of f (RH) fit for back scattering at 700 nm
167. Conf90_700bsp_DN: Confidence width in value of f (RH=90%) for back scattering at 700 nm
168. DNfitfRH_450sp_35: f (RH=35%) value for total scattering at 450 nm
169. DNfitfRH_450sp_45: f (RH=45%) value for total scattering at 450 nm
170. DNfitfRH_450sp_50: f (RH=50 %) value for total scattering at 450 nm
171. DNfitfRH_450sp_60: f (RH=60%) value for total scattering at 450 nm
172. DNfitfRH_450sp_65: f (RH=65%) value for total scattering at 450 nm
173. DNfitfRH_450sp_70: f (RH=70%) value for total scattering at 450 nm
174. DNfitfRH_450sp_75: f (RH=75%) value for total scattering at 450 nm
175. DNfitfRH_450sp_80: f (RH=80%) value for total scattering at 450 nm
176. DNfitfRH_450sp_82: f (RH=82%) value for total scattering at 450 nm
177. DNfitfRH_450sp_85: f (RH=85%) value for total scattering at 450 nm
178. DNfitfRH_550sp_35: f (RH=35%) value for total scattering at 550 nm
179. DNfitfRH_550sp_45: f (RH=45%) value for total scattering at 550 nm
180. DNfitfRH_550sp_50: f (RH=50%) value for total scattering at 550 nm
181. DNfitfRH_550sp_60: f (RH=60%) value for total scattering at 550 nm
182. DNfitfRH_550sp_65: f (RH=65%) value for total scattering at 550 nm
183. DNfitfRH_550sp_70: f (RH=70%) value for total scattering at 550 nm
184. DNfitfRH_550sp_75: f (RH=75%) value for total scattering at 550 nm
185. DNfitfRH_550sp_80: f (RH=80%) value for total scattering at 550 nm
186. DNfitfRH_550sp_82: f (RH=82%) value for total scattering at 550 nm
187. DNfitfRH_550sp_85: f (RH=85%) value for total scattering at 550 nm
188. DNfitfRH_700sp_35: f (RH=35%) value for total scattering at 700 nm
189. DNfitfRH_700sp_45: f (RH=45%) value for total scattering at 700 nm
190. DNfitfRH_700sp_50: f (RH=50%) value for total scattering at 700 nm
191. DNfitfRH_700sp_60: f (RH=60%) value for total scattering at 700 nm
192. DNfitfRH_700sp_65: f (RH=65%) value for total scattering at 700 nm
193. DNfitfRH_700sp_70: f (RH=70%) value for total scattering at 700 nm
194. DNfitfRH_700sp_75: f (RH=75%) value for total scattering at 700 nm
195. DNfitfRH_700sp_80: f (RH=80%) value for total scattering at 700 nm
196. DNfitfRH_700sp_82: f (RH=82%) value for total scattering at 700 nm
197. DNfitfRH_700sp_85: f (RH=85%) value for total scattering at 700 nm
198. DNfitfRH_450bsp_35: f (RH=35%) value for back scattering at 450 nm
199. DNfitfRH_450bsp_45: f (RH=45%) value for back scattering at 450 nm
200. DNfitfRH_450bsp_50: f (RH=50%) value for back scattering at 450 nm
201. DNfitfRH_450bsp_60: f (RH=60%) value for back scattering at 450 nm
202. DNfitfRH_450bsp_65: f (RH=65%) value for back scattering at 450 nm
203. DNfitfRH_450bsp_70: f (RH=70%) value for back scattering at 450 nm
204. DNfitfRH_450bsp_75: f (RH=75%) value for back scattering at 450 nm
205. DNfitfRH_450bsp_80: f (RH=80%) value for back scattering at 450 nm
206. DNfitfRH_450bsp_82: f (RH=82%) value for back scattering at 450 nm
207. DNfitfRH_450bsp_85: f (RH=85%) value for back scattering at 450 nm
208. DNfitfRH_550bsp_35: f (RH=35%) value for back scattering at 550 nm
209. DNfitfRH_550bsp_45: f (RH=45%) value for back scattering at 550 nm
210. DNfitfRH_550bsp_50: f (RH=50%) value for back scattering at 550 nm
211. DNfitfRH_550bsp_60: f (RH=60%) value for back scattering at 550 nm
212. DNfitfRH_550bsp_65: f (RH=65%) value for back scattering at 550 nm
213. DNfitfRH_550bsp_70: f (RH=70%) value for back scattering at 550 nm
214. DNfitfRH_550bsp_75: f (RH=75%) value for back scattering at 550 nm
215. DNfitfRH_550bsp_80: f (RH=80%) value for back scattering at 550 nm
216. DNfitfRH_550bsp_82: f (RH=82%) value for back scattering at 550 nm
217. DNfitfRH_550bsp_85: f (RH=85%) value for back scattering at 550 nm
218. DNfitfRH_700bsp_35: f (RH=35%) value for back scattering at 700 nm
219. DNfitfRH_700bsp_45: f (RH=45%) value for back scattering at 700 nm
220. DNfitfRH_700bsp_50: f (RH=50%) value for back scattering at 700 nm
221. DNfitfRH_700bsp_60: f (RH=60%) value for back scattering at 700 nm
222. DNfitfRH_700bsp_65: f (RH=65%) value for back scattering at 700 nm
223. DNfitfRH_700bsp_70: f (RH=70%) value for back scattering at 700 nm
224. DNfitfRH_700bsp_75: f (RH=75%) value for back scattering at 700 nm
225. DNfitfRH_700bsp_80: f (RH=80%) value for back scattering at 700 nm
226. DNfitfRH_700bsp_82: f (RH=82%) value for back scattering at 700 nm
227. DNfitfRH_700bsp_85: f (RH=85%) value for back scattering at 700 nm
228. drysp_450_AMB (1/Mm) Low RH ambient scattering at 450 nm (scattering at ambient T and P
conditions at RH = RH_ReferenceNeph)
229. devdrysp_450_AMB (1/Mm) Standard deviation for drysp_450_AMB
230. drysp_550_AMB (1/Mm) Low RH ambient scattering at 550 nm
231. devdrysp_550_AMB (1/Mm) Standard deviation for drysp_550_AMB
232. drysp_700_AMB (1/Mm) Low RH ambient scattering at 700 nm
233. devdrysp_700_AMB (1/Mm) Standard deviation for drybsp_700_AMB
234. drybsp_450_AMB (1/Mm) Low RH ambient back scattering at 450 nm
235. devdrybsp_450_AMB (1/Mm) Standard deviation for drybsp_450_AMB
236. drybsp_550_AMB (1/Mm) Low RH ambient back scattering at 550 nm
237. devdrybsp_550_AMB (1/Mm) Standard deviation for drybsp_550_AMB
238. drybsp_700_AMB (1/Mm) Low RH ambient back scattering at 700 nm
239. devdrybsp_7000_AMB (1/Mm) Standard deviation for drybsp_700_AMB
240. f(RHamb)_sp450: f(RH=ambient) value for total scattering at 450 nm
241. f(RHamb)_sp550: f(RH=ambient) value for total scattering at 550 nm
242. f(RHamb)_sp700: f(RH=ambient) value for total scattering at 700 nm
243. f(RHamb)_bsp450: f(RH=ambient) value for back scattering at 450 nm
244. f(RHamb)_bsp550: f(RH=ambient) value for back scattering at 550 nm
245. f(RHamb)_bsp700: f(RH=ambient) value for back scattering at 700 nm
5.0 DATA REMARKS
a Fit root mean square error: the root mean square error of the regression,
which is calculated as the square root of the sum of squares of residuals
(difference between observed and predicted value) divided by degrees of freedom.
A value closer to zero means a better fit.
b Confidence width: defines the width of the confidence interval for the
predicted value with a 95% certainty. It means there is a 95% probability that
the predicted value actually is within lower (associated value-confidence width)
and upper (associated value + confidence width) limit of the confidence
interval. For example, an f(RH) value of 2 with a confidence width of 0.3
indicates that the f(RH) value can be between 1.7 and 2.3 with a 95% confidence
limit.
6.0 REFERENCES
Carrico, C.M., M.J. Rood, and J.A. Ogren, Light scattering properties at Cape Grim,
Tasmania, during the First Aerosol Characterization Experiment, J. Geophys. Res., 103,
D13, 16,565-16,574, 1998.
Carrico, C.M., M.J. Rood, J.A. Ogren, C. Neususs, A. Wiedensohler, and J.
Heintzenberg, Aerosol optical properties at Sagres, Portugal, during ACE-2, Tellus, 52B,
694-716, 2000.
Kotchenruther, R.A., P.V. Hobbs, and D.A. Hegg, Humidification factors for atmospheric
aerosols off the mid-Atlantic coast of the United States, J. Geophys. Res., 104, D2, 2239-
2251, 1999.
Actually is around 36%
I think it would be good to note that fits for decreasing controlled RH pathway in a Deliquescent type
of growth is valid until CRH+5%.