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| 1 The SCC netCDF file format | |
| 2 ========================== | |
| 3 | |
| 4 Rationale | |
| 5 --------- | |
| 6 | |
| 7 The Single Calculus Chain (SCC) is composed by two different modules: | |
| 8 | |
| 9 - pre-processing module ( scc\_preprocessing) | |
| 10 | |
| 11 - optical processing module ( ELDA) | |
| 12 | |
| 13 To perfom aerosol optical retrievals the SCC needs not only the raw | |
| 14 lidar data but also a certain number of parameters to use in both | |
| 15 pre-processing and optical processing stages. The SCC gets these | |
| 16 parameters looking at two different locations: | |
| 17 | |
| 18 - Single Calculus Chain relational database (SCC\_DB) | |
| 19 | |
| 20 - Input files | |
| 21 | |
| 22 There are some paramenters that can be found only in the input files | |
| 23 (those ones changing from measurement to measurement), others that can | |
| 24 be found only in the SCC\_DB and other ones that can be found in both | |
| 25 these locations. In the last case, if a particular parameter is needed, | |
| 26 the SCC will search first in the input files and then in SCC\_DB. If the | |
| 27 parameter is found in the input files the SCC will keep it without | |
| 28 looking into SCC\_DB. | |
| 29 | |
| 30 The input files have to be submitted to the SCC in NetCDF format. At the | |
| 31 present the SCC can handle four different types of input files: | |
| 32 | |
| 33 1. Raw Lidar Data | |
| 34 2. Sounding Data | |
| 35 3. Overlap | |
| 36 4. Lidar Ratio | |
| 37 | |
| 38 | |
| 39 As already mentioned, the Raw Lidar Data file contains not only the | |
| 40 raw lidar data but also other parameters to use to perform the | |
| 41 pre-processing and optical processing. The Sounding Data file | |
| 42 contains the data coming from a correlative radiosounding and it is used | |
| 43 by the SCC for molecular density calculation. The Overlap file | |
| 44 contains the measured overlap function. The Lidar Ratio file contains | |
| 45 a lidar ratio profile to use in elastic backscatter retrievals. The | |
| 46 Raw Lidar Data file is of course mandatory and the Sounding Data, | |
| 47 Overlap and Lidar Ratio files are optional. If Sounding Data file | |
| 48 is not submitted by the user, the molecular density will be calculated | |
| 49 by the SCC using the “US Standard Atmosphere 1976”. If the Overlap | |
| 50 file is not submitted by the user, the SCC will get the full overlap | |
| 51 height from SCC\_DB and it will produce optical results starting from | |
| 52 this height. If Lidar Ratio file is not submitted by the user, the | |
| 53 SCC will consider a fixed value for lidar ratio got from SCC\_DB. | |
| 54 | |
| 55 The user can decide to submit all these files or any number of them (of | |
| 56 course the file Raw Lidar Data is mandatory). For example the user | |
| 57 can submit together with the Raw Lidar Data file only the Sounding | |
| 58 Data file or only the Overlap file. | |
| 59 | |
| 60 This document provides a detailed explanation about the structure of the | |
| 61 NetCDF input files to use for SCC data submission. All Earlinet groups | |
| 62 should read it carefully because they have to produce such kind of input | |
| 63 files if they want to use the SCC for their standard lidar retrievals. | |
| 64 Every comments or suggestions regarding this document can be sent to | |
| 65 Giuseppe D’Amico by e-mail at ``damico@imaa.cnr.it`` | |
| 66 | |
| 67 This document is available for downloading at ``www.earlinetasos.org`` | |
| 68 | |
| 69 In table tab:rawdata is reported a list of dimensions, variables and | |
| 70 global attributes that can be used in the NetCDF Raw Lidar Data input | |
| 71 file. For each of them it is indicated: | |
| 72 | |
| 73 - The name. For the multidimensional variables also the corresponding | |
| 74 dimensions are reported | |
| 75 | |
| 76 - A description explaining the meaning | |
| 77 | |
| 78 - The type | |
| 79 | |
| 80 - If it is mandatory or optional | |
| 81 | |
| 82 As already mentioned, the SCC can get some parameters looking first in | |
| 83 the Raw Lidar Data input file and then into SCC\_DB. This means that | |
| 84 to use the parameters stored in SCC\_DB the optional variables or | |
| 85 optional global attributes must not appear within Raw Lidar Data | |
| 86 file. This is the suggested and recommended way to use the SCC. Please | |
| 87 include optional parameters in the Raw Lidar Data only as an | |
| 88 exception. | |
| 89 | |
| 90 In table tab:sounding, tab:overlap and tab:lr are reported all the | |
| 91 information about the structure of Sounding Data, Overlap and | |
| 92 Lidar Ratio input files respectively. | |
| 93 | |
| 94 Example | |
| 95 ------- | |
| 96 | |
| 97 Let’s now consider an example of Raw Lidar Data input file. Suppose | |
| 98 we want to generate NetCDF input file corresponding to a measurement | |
| 99 with the following properties: | |
| 100 | |
| 101 +----------------------+-------------------------------------------+ | |
| 102 | Start Date | :math:`30^{th}` January 2009 | | |
| 103 +----------------------+-------------------------------------------+ | |
| 104 | Start Time UT | 00:00:01 | | |
| 105 +----------------------+-------------------------------------------+ | |
| 106 | Stop Time UT | 00:05:01 | | |
| 107 +----------------------+-------------------------------------------+ | |
| 108 | Station Name | Dummy station | | |
| 109 +----------------------+-------------------------------------------+ | |
| 110 | Earlinet call-sign | cc | | |
| 111 +----------------------+-------------------------------------------+ | |
| 112 | Pointing angle | 5 degrees with respect to the zenith | | |
| 113 +----------------------+-------------------------------------------+ | |
| 114 | |
| 115 Moreover suppose that this measurement is composed by the following | |
| 116 lidar channels: | |
| 117 | |
| 118 1. 1064 lidar channel | |
| 119 | |
| 120 +------------------------------+-------------------------------+ | |
| 121 | Emission wavelength=1064nm | Detection wavelength=1064nm | | |
| 122 +------------------------------+-------------------------------+ | |
| 123 | Time resolution=30s | Number of laser shots=1500 | | |
| 124 +------------------------------+-------------------------------+ | |
| 125 | Number of bins=3000 | Detection mode=analog | | |
| 126 +------------------------------+-------------------------------+ | |
| 127 | Range resolution=7.5m | Polarization state=total | | |
| 128 +------------------------------+-------------------------------+ | |
| 129 | |
| 130 2. 532 cross lidar channel | |
| 131 | |
| 132 +-----------------------------+---------------------------------+ | |
| 133 | Emission wavelength=532nm | Detection wavelength=532nm | | |
| 134 +-----------------------------+---------------------------------+ | |
| 135 | Time resolution=60s | Number of laser shots=3000 | | |
| 136 +-----------------------------+---------------------------------+ | |
| 137 | Number of bins=5000 | Detection mode=photoncounting | | |
| 138 +-----------------------------+---------------------------------+ | |
| 139 | Range resolution=15m | Polarization state=cross | | |
| 140 +-----------------------------+---------------------------------+ | |
| 141 | |
| 142 3. 532 parallel lidar channel | |
| 143 | |
| 144 +-----------------------------+---------------------------------+ | |
| 145 | Emission wavelength=532nm | Detection wavelength=532nm | | |
| 146 +-----------------------------+---------------------------------+ | |
| 147 | Time resolution=60s | Number of laser shots=3000 | | |
| 148 +-----------------------------+---------------------------------+ | |
| 149 | Number of bins=5000 | Detection mode=photoncounting | | |
| 150 +-----------------------------+---------------------------------+ | |
| 151 | Range resolution=15m | Polarization state=parallel | | |
| 152 +-----------------------------+---------------------------------+ | |
| 153 | |
| 154 4. 607 :math:`N_2` vibrational Raman channel | |
| 155 | |
| 156 +-----------------------------+---------------------------------+ | |
| 157 | Emission wavelength=532nm | Detection wavelength=607nm | | |
| 158 +-----------------------------+---------------------------------+ | |
| 159 | Time resolution=60s | Number of laser shots=3000 | | |
| 160 +-----------------------------+---------------------------------+ | |
| 161 | Number of bins=5000 | Detection mode=photoncounting | | |
| 162 +-----------------------------+---------------------------------+ | |
| 163 | Range resolution=15m | | |
| 164 +-----------------------------+---------------------------------+ | |
| 165 | |
| 166 Finally let’s assume we have also performed dark measurements before the | |
| 167 lidar measurements from the 23:50:01 UT up to 23:53:01 UT of | |
| 168 29:math:`^\mathrmth` January 2009. | |
| 169 | |
| 170 Dimensions | |
| 171 ~~~~~~~~~~ | |
| 172 | |
| 173 Looking at table tab:rawdata we have to fix the following dimensions: | |
| 174 | |
| 175 :: | |
| 176 | |
| 177 points | |
| 178 channels | |
| 179 time | |
| 180 nb_of_time_scales | |
| 181 scan_angles | |
| 182 time_bck | |
| 183 | |
| 184 The dimension ``time`` is unlimited so we don’t have to fix it. | |
| 185 | |
| 186 We have 4 lidar channels so: | |
| 187 | |
| 188 :: | |
| 189 | |
| 190 channels=4 | |
| 191 | |
| 192 Regarding the dimension ``points`` we have only one channel with a | |
| 193 number of vertical bins equal to 3000 (the 1064nm) and all other | |
| 194 channels with 5000 vertical bins. In cases like this the dimension | |
| 195 ``points`` has to be fixed to the maximum number of vertical bins so: | |
| 196 | |
| 197 :: | |
| 198 | |
| 199 points=5000 | |
| 200 | |
| 201 Moreover only one channel (1064nm) is acquired with a time resolution of | |
| 202 30 seconds, all the other channels have a time resolution of 60 seconds. | |
| 203 This means that we have to define two different time scales. We have to | |
| 204 set: | |
| 205 | |
| 206 :: | |
| 207 | |
| 208 nb_of_time_scales=2 | |
| 209 | |
| 210 The measurement is performed only at one scan angle (5 degrees with | |
| 211 respect to the zenith) so: | |
| 212 | |
| 213 :: | |
| 214 | |
| 215 scan_angles=1 | |
| 216 | |
| 217 We have 3 minutes of dark measurements and two different time scales one | |
| 218 with 60 seconds time resolution and the other one with 30 seconds time | |
| 219 resolution. So we will have 3 different dark profiles for the channels | |
| 220 acquired with the first time scale and 6 for the lidar channels acquired | |
| 221 with the second time scale. We have to fix the dimension ``time_bck`` as | |
| 222 the maximum between these values: | |
| 223 | |
| 224 :: | |
| 225 | |
| 226 time_bck=6 | |
| 227 | |
| 228 Variables | |
| 229 ~~~~~~~~~ | |
| 230 | |
| 231 In this section it will be explained how to fill all the possible | |
| 232 variables either mandatory or optional of Raw Lidar Data input file. | |
| 233 | |
| 234 Raw_Data_Start_Time(time, nb_of_time_scales) | |
| 235 This 2 dimensional mandatory array has to contain the acquisition | |
| 236 start time (in seconds from the time given by the global attribute | |
| 237 ``RawData_Start_Time_UT``) of each lidar profile. In this example we | |
| 238 have two different time scales: one is characterized by steps of 30 | |
| 239 seconds (the 1064nm is acquired with this time scale) the other by | |
| 240 steps of 60 seconds (532cross, 532parallel and 607nm). Moreover the | |
| 241 measurement start time is 00:00:01 UT and the measurement stop time | |
| 242 is 00:05:01 UT. In this case we have to define: | |
| 243 | |
| 244 :: | |
| 245 | |
| 246 Raw_Data_Start_Time = | |
| 247 0, 0, | |
| 248 60, 30, | |
| 249 120, 60, | |
| 250 180, 90, | |
| 251 240, 120, | |
| 252 _, 150, | |
| 253 _, 180, | |
| 254 _, 210, | |
| 255 _, 240, | |
| 256 _, 270 ; | |
| 257 | |
| 258 The order used to fill this array defines the correspondence between | |
| 259 the different time scales and the time scale index. In this example | |
| 260 we have a time scale index of 0 for the time scale with steps of 60 | |
| 261 seconds and a time scale index of 1 for the other one. | |
| 262 | |
| 263 Raw_Data_Stop_Time(time, nb_of_time_scales) | |
| 264 The same as previous item but for the data acquisition stop time. | |
| 265 Following a similar procedure we have to define: | |
| 266 | |
| 267 :: | |
| 268 | |
| 269 Raw_Data_Stop_Time = | |
| 270 60, 30, | |
| 271 120, 60, | |
| 272 180, 90, | |
| 273 240, 120, | |
| 274 300, 150, | |
| 275 _, 180, | |
| 276 _, 210, | |
| 277 _, 240, | |
| 278 _, 270, | |
| 279 _, 300 ; | |
| 280 | |
| 281 Raw_Lidar_Data(time, channels, points) | |
| 282 This 3 dimensional mandatory array has to be filled with the | |
| 283 time-series of raw lidar data. The photoncounting profiles have to | |
| 284 submitted in counts (so as integers) while the analog ones in mV. The | |
| 285 order the user chooses to fill this array defines the correspondence | |
| 286 between channel index and lidar data. | |
| 287 | |
| 288 For example if we fill this array in such way that: | |
| 289 | |
| 290 +-------------------------------------+------------------------------------------------------------+ | |
| 291 | Raw_Lidar_Data(time,0,points | :math:`\rightarrow` is the time-series of 1064 nm | | |
| 292 +-------------------------------------+------------------------------------------------------------+ | |
| 293 | Raw_Lidar_Data(time,1,points | :math:`\rightarrow` is the time-series of 532 cross | | |
| 294 +-------------------------------------+------------------------------------------------------------+ | |
| 295 | Raw_Lidar_Data(time,2,points | :math:`\rightarrow` is the time-series of 532 parallel | | |
| 296 +-------------------------------------+------------------------------------------------------------+ | |
| 297 | Raw_Lidar_Data(time,3,points | :math:`\rightarrow` is the time-series of 607 nm | | |
| 298 +-------------------------------------+------------------------------------------------------------+ | |
| 299 | |
| 300 from now on the channel index 0 is associated to the 1064 channel, | |
| 301 1 to the 532 cross, 2 to the 532 parallel and 3 to the 607nm. | |
| 302 | |
| 303 Raw_Bck_Start_Time(time_bck, nb_of_time_scales) | |
| 304 This 2 dimensional optional array has to contain the acquisition | |
| 305 start time (in seconds from the time given by the global attribute | |
| 306 ``RawBck_Start_Time_UT``) of each dark measurements profile. | |
| 307 Following the same procedure used for the variable | |
| 308 ``Raw_Data_Start_Time`` we have to define: | |
| 309 | |
| 310 :: | |
| 311 | |
| 312 Raw_Bck_Start_Time = | |
| 313 0, 0, | |
| 314 60, 30, | |
| 315 120, 60, | |
| 316 _, 90, | |
| 317 _, 120, | |
| 318 _, 150; | |
| 319 | |
| 320 Raw_Bck_Stop_Time(time_bck, nb_of_time_scales) | |
| 321 The same as previous item but for the dark acquisition stop time. | |
| 322 Following a similar procedure we have to define: | |
| 323 | |
| 324 :: | |
| 325 | |
| 326 Raw_Bck_Stop_Time = | |
| 327 60, 30, | |
| 328 120, 60, | |
| 329 180, 90, | |
| 330 _, 120, | |
| 331 _, 150, | |
| 332 _, 180 ; | |
| 333 | |
| 334 | |
| 335 Background_Profile(time_bck, channels, points) | |
| 336 This 3 dimensional optional array has to be filled with the | |
| 337 time-series of the dark measurements data. The photoncounting | |
| 338 profiles have to submitted in counts (so as integers) while the | |
| 339 analog ones in mV. The user has to fill this array following the same | |
| 340 order used in filling the array ``Raw_Lidar_Data``: | |
| 341 | |
| 342 +---------------------------------------------+----------------------------------------------------------+ | |
| 343 | Background_Profile(time_bck,0,points | :math:`\rightarrow` dark time-series at 1064 nm | | |
| 344 +---------------------------------------------+----------------------------------------------------------+ | |
| 345 | Background_Profile(time_bck,1,points | :math:`\rightarrow` dark time-series at 532 cross | | |
| 346 +---------------------------------------------+----------------------------------------------------------+ | |
| 347 | Background_Profile(time_bck,2,points | :math:`\rightarrow` dark time-series at 532 parallel | | |
| 348 +---------------------------------------------+----------------------------------------------------------+ | |
| 349 | Background_Profile(time_bck,3,points | :math:`\rightarrow` dark time-series at 607 nm | | |
| 350 +---------------------------------------------+----------------------------------------------------------+ | |
| 351 | |
| 352 | |
| 353 channel_ID(channels) | |
| 354 This mandatory array provides the link between the channel index | |
| 355 within the Raw Lidar Data input file and the channel ID in | |
| 356 SCC\_DB. To fill this variable the user has to know which channel IDs | |
| 357 in SCC\_DB correspond to his lidar channels. For this purpose the | |
| 358 SCC, in its final version will provide to the user a special tool to | |
| 359 get these channel IDs through a Web interface. At the moment this | |
| 360 interface is not yet available and these channel IDs will be | |
| 361 communicated directly to the user by the NA5 people. | |
| 362 | |
| 363 Anyway to continue the example let’s suppose that the four lidar | |
| 364 channels taken into account are mapped into SCC\_DB with the | |
| 365 following channel IDs: | |
| 366 | |
| 367 +----------------+--------------------------------------+ | |
| 368 | 1064 nm | :math:`\rightarrow` channel ID=7 | | |
| 369 +----------------+--------------------------------------+ | |
| 370 | 532 cross | :math:`\rightarrow` channel ID=5 | | |
| 371 +----------------+--------------------------------------+ | |
| 372 | 532 parallel | :math:`\rightarrow` channel ID=6 | | |
| 373 +----------------+--------------------------------------+ | |
| 374 | 607 nm | :math:`\rightarrow` channel ID=8 | | |
| 375 +----------------+--------------------------------------+ | |
| 376 | |
| 377 In this case we have to define: | |
| 378 | |
| 379 :: | |
| 380 | |
| 381 channel_ID = 7, 5, 6, 8 ; | |
| 382 | |
| 383 id_timescale(channels) | |
| 384 This mandatory array is introduced to determine which time scale is | |
| 385 used for the acquisition of each lidar channel. In particular this | |
| 386 array defines the link between the channel index and the time scale | |
| 387 index. In our example we have two different time scales. Filling the | |
| 388 arrays ``Raw_Data_Start_Time`` and ``Raw_Data_Stop_Time`` we have | |
| 389 defined a time scale index of 0 for the time scale with steps of 60 | |
| 390 seconds and a time scale index of 1 for the other one with steps of | |
| 391 30 seconds. In this way this array has to be set as: | |
| 392 | |
| 393 :: | |
| 394 | |
| 395 id_timescale = 1, 0, 0, 0 ; | |
| 396 | |
| 397 Laser_Pointing_Angle(scan_angles | |
| 398 This mandatory array contains all the scan angles used in the | |
| 399 measurement. In our example we have only one scan angle of 5 degrees | |
| 400 with respect to the zenith, so we have to define: | |
| 401 | |
| 402 :: | |
| 403 | |
| 404 Laser_Pointing_Angle = 5 ; | |
| 405 | |
| 406 Laser_Pointing_Angle_of_Profiles(time, nb_of_time_scales) | |
| 407 This mandatory array is introduced to determine which scan angle is | |
| 408 used for the acquisition of each lidar profile. In particular this | |
| 409 array defines the link between the time and time scales indexes and | |
| 410 the scan angle index. In our example we have a single scan angle that | |
| 411 has to correspond to the scan angle index 0. So this array has to be | |
| 412 defined as: | |
| 413 | |
| 414 :: | |
| 415 | |
| 416 Laser_Pointing_Angle_of_Profiles = | |
| 417 0, 0, | |
| 418 0, 0, | |
| 419 0, 0, | |
| 420 0, 0, | |
| 421 0, 0, | |
| 422 _, 0, | |
| 423 _, 0, | |
| 424 _, 0, | |
| 425 _, 0, | |
| 426 _, 0 ; | |
| 427 | |
| 428 Laser_Shots(time, channels) | |
| 429 This mandatory array stores the laser shots accumulated at each time | |
| 430 for each channel. In our example the number of laser shots | |
| 431 accumulated is 1500 for the 1064nm channels and 3000 for all the | |
| 432 other channels. Moreover the laser shots do not change with the time. | |
| 433 So we have to define this array as: | |
| 434 | |
| 435 :: | |
| 436 | |
| 437 Laser_Shots = | |
| 438 1500, 3000, 3000, 3000, | |
| 439 1500, 3000, 3000, 3000, | |
| 440 1500, 3000, 3000, 3000, | |
| 441 1500, 3000, 3000, 3000, | |
| 442 1500, 3000, 3000, 3000, | |
| 443 1500, _, _, _, | |
| 444 1500, _, _, _, | |
| 445 1500, _, _, _, | |
| 446 1500, _, _, _, | |
| 447 1500, _, _, _ ; | |
| 448 | |
| 449 Emitted_Wavelength(channels) | |
| 450 This optional array defines the link between the channel index and | |
| 451 the emission wavelength for each lidar channel. The wavelength has to | |
| 452 be expressed in nm. This information can be also taken from SCC\_DB. | |
| 453 In our example we have: | |
| 454 | |
| 455 :: | |
| 456 | |
| 457 Emitted_Wavelength = 1064, 532, 532, 532 ; | |
| 458 | |
| 459 Detected_Wavelength(channels) | |
| 460 This optional array defines the link between the channel index and | |
| 461 the detected wavelength for each lidar channel. Here detected | |
| 462 wavelength means the value of center of interferential filter | |
| 463 expressed in nm. This information can be also taken from SCC\_DB. In | |
| 464 our example we have: | |
| 465 | |
| 466 :: | |
| 467 | |
| 468 Detected_Wavelength = 1064, 532, 532, 607 ; | |
| 469 | |
| 470 Raw_Data_Range_Resolution(channels) | |
| 471 This optional array defines the link between the channel index and | |
| 472 the raw range resolution for each channel. If the scan angle is | |
| 473 different from zero this quantity is different from the vertical | |
| 474 resolution. More precisely if :math:`\alpha` is the scan angle used | |
| 475 and :math:`\Delta z` is the range resolution the vertical | |
| 476 resolution is calculated as :math:`\Delta | |
| 477 z'=\Delta z \cos\alpha`. This array has to be filled with | |
| 478 :math:`\Delta z` and not with :math:`\Delta z'`. The unit is | |
| 479 meters. This information can be also taken from SCC\_DB. In our | |
| 480 example we have: | |
| 481 | |
| 482 :: | |
| 483 | |
| 484 Raw_Data_Range_Resolution = 7.5, 15.0, 15.0, 15.0 ; | |
| 485 | |
| 486 ID_Range(channels) | |
| 487 This optional array defines if a particular channel is configured as | |
| 488 high, low or ultranear range channel. In particular a value 0 | |
| 489 indicates a low range channel, a value 1 a high range channel and a | |
| 490 value of 2 an ultranear range channel. If for a particular channel | |
| 491 you don’t separate between high and low range channel, please set the | |
| 492 corresponding value to 1. This information can be also taken from | |
| 493 SCC\_DB. In our case we have to set: | |
| 494 | |
| 495 :: | |
| 496 | |
| 497 ID_Range = 1, 1, 1, 1 ; | |
| 498 | |
| 499 Scattering_Mechanism(channels) | |
| 500 This optional array defines the scattering mechanism involved in | |
| 501 each lidar channel. In particular the following values are adopted: | |
| 502 | |
| 503 +------+---------------------------------------------------------------------------------------------+ | |
| 504 | 0 | :math:`\rightarrow` Total elastic backscatter | | |
| 505 +------+---------------------------------------------------------------------------------------------+ | |
| 506 | 1 | :math:`\rightarrow` :math:`N_2` vibrational Raman backscatter | | |
| 507 +------+---------------------------------------------------------------------------------------------+ | |
| 508 | 2 | :math:`\rightarrow` Cross polarization elastic backscatter | | |
| 509 +------+---------------------------------------------------------------------------------------------+ | |
| 510 | 3 | :math:`\rightarrow` Parallel polarization elastic backscatter | | |
| 511 +------+---------------------------------------------------------------------------------------------+ | |
| 512 | 4 | :math:`\rightarrow` :math:`H_2O` vibrational Raman backscatter | | |
| 513 +------+---------------------------------------------------------------------------------------------+ | |
| 514 | 5 | :math:`\rightarrow` Rotational Raman Stokes line close to elastic line | | |
| 515 +------+---------------------------------------------------------------------------------------------+ | |
| 516 | 6 | :math:`\rightarrow` Rotational Raman Stokes line far from elastic line | | |
| 517 +------+---------------------------------------------------------------------------------------------+ | |
| 518 | 7 | :math:`\rightarrow` Rotational Raman anti-Stokes line close to elastic line | | |
| 519 +------+---------------------------------------------------------------------------------------------+ | |
| 520 | 8 | :math:`\rightarrow` Rotational Raman anti-Stokes line far from elastic line | | |
| 521 +------+---------------------------------------------------------------------------------------------+ | |
| 522 | 9 | :math:`\rightarrow` Rotational Raman Stokes and anti-Stokes lines close to elastic line | | |
| 523 +------+---------------------------------------------------------------------------------------------+ | |
| 524 | 10 | :math:`\rightarrow` Rotational Raman Stokes and anti-Stokes lines far from elastic line | | |
| 525 +------+---------------------------------------------------------------------------------------------+ | |
| 526 | |
| 527 This information can be also taken from SCC\_DB. In our example we have: | |
| 528 | |
| 529 :: | |
| 530 | |
| 531 Scattering_Mechanism = 0, 2, 3, 1 ; | |
| 532 | |
| 533 Acquisition_Mode(channels) | |
| 534 This optional array defines the acquisition mode (analog or | |
| 535 photoncounting) involved in each lidar channel. In particular a value | |
| 536 of 0 means analog mode and 1 photoncounting mode. This information | |
| 537 can be also taken from SCC\_DB. In our example we have: | |
| 538 | |
| 539 :: | |
| 540 | |
| 541 Acquisition_Mode = 0, 1, 1, 1 ; | |
| 542 | |
| 543 Laser_Repetition_Rate(channels) | |
| 544 This optional array defines the repetition rate in Hz used to | |
| 545 acquire each lidar channel. This information can be also taken from | |
| 546 SCC\_DB. In our example we are supposing we have only one laser with | |
| 547 a repetition rate of 50 Hz so we have to set: | |
| 548 | |
| 549 :: | |
| 550 | |
| 551 Laser_Repetition_Rate = 50, 50, 50, 50 ; | |
| 552 | |
| 553 Dead_Time(channels) | |
| 554 This optional array defines the dead time in ns associated to each | |
| 555 lidar channel. The SCC will use the values given by this array to | |
| 556 correct the photoncounting signals for dead time. Of course for | |
| 557 analog signals no dead time correction will be applied (for analog | |
| 558 channels the corresponding dead time values have to be set to | |
| 559 undefined value). This information can be also taken from SCC\_DB. In | |
| 560 our example the 1064 nm channel is acquired in analog mode so the | |
| 561 corresponding dead time value has to be undefined. If we suppose a | |
| 562 dead time of 10 ns for all other channels we have to set: | |
| 563 | |
| 564 :: | |
| 565 | |
| 566 Dead_Time = _, 10, 10, 10 ; | |
| 567 | |
| 568 Dead_Time_Corr_Type(channels | |
| 569 This optional array defines which kind of dead time correction has | |
| 570 to be applied on each photoncounting channel. The SCC will correct | |
| 571 the data supposing a not-paralyzable channel if a value of 0 is found | |
| 572 while a paralyzable channel is supposed if a value of 1 is found. Of | |
| 573 course for analog signals no dead time correction will be applied and | |
| 574 so the corresponding values have to be set to undefined value. This | |
| 575 information can be also taken from SCC\_DB. In our example the 1064 | |
| 576 nm channel is acquired in analog mode so the corresponding has to be | |
| 577 undefined. If we want to consider all the photoncounting signals as | |
| 578 not-paralyzable ones: we have to set: | |
| 579 | |
| 580 :: | |
| 581 | |
| 582 Dead_Time_Corr_Type = _, 0, 0, 0 ; | |
| 583 | |
| 584 Trigger_Delay(channels) | |
| 585 This optional array defines the delay (in ns) of the middle of the | |
| 586 first rangebin with respect to the output laser pulse for each lidar | |
| 587 channel. The SCC will use the values given by this array to correct | |
| 588 for trigger delay. This information can be also taken from SCC\_DB. | |
| 589 Let’s suppose that in our example all the photoncounting channels are | |
| 590 not affected by this delay and only the analog channel at 1064nm is | |
| 591 acquired with a delay of 50ns. In this case we have to set: | |
| 592 | |
| 593 :: | |
| 594 | |
| 595 Trigger_Delay = 50, 0, 0, 0 ; | |
| 596 | |
| 597 Background_Mode(channels | |
| 598 This optional array defines how the atmospheric background has to be | |
| 599 subtracted from the lidar channel. Two options are available for the | |
| 600 calculation of atmospheric background: | |
| 601 | |
| 602 #. Average in the far field of lidar channel. In this case the value | |
| 603 of this variable has to be 1 | |
| 604 | |
| 605 #. Average within pre-trigger bins. In this case the value of this | |
| 606 variable has to be 0 | |
| 607 | |
| 608 This information can be also taken from SCC\_DB. Let’s suppose in our | |
| 609 example we use the pre-trigger for the 1064nm channel and the far | |
| 610 field for all other channels. In this case we have to set: | |
| 611 | |
| 612 :: | |
| 613 | |
| 614 Background_Mode = 0, 1, 1, 1 ; | |
| 615 | |
| 616 Background_Low(channels) | |
| 617 This mandatory array defines the minimum altitude (in meters) to | |
| 618 consider in calculating the atmospheric background for each channel. | |
| 619 In case pre-trigger mode is used the corresponding value has to be | |
| 620 set to the rangebin to be used as lower limit (within pre-trigger | |
| 621 region) for background calculation. In our example, if we want to | |
| 622 calculate the background between 30000 and 50000 meters for all | |
| 623 photoncounting channels and we want to use the first 500 pre-trigger | |
| 624 bins for the background calculation for the 1064nm channel we have to | |
| 625 set: | |
| 626 | |
| 627 :: | |
| 628 | |
| 629 Background_Low= 0, 30000, 30000, 30000 ; | |
| 630 | |
| 631 Background_High(channels) | |
| 632 This mandatory array defines the maximum altitude (in meters) to | |
| 633 consider in calculating the atmospheric background for each channel. | |
| 634 In case pre-trigger mode is used the corresponding value has to be | |
| 635 set to the rangebin to be used as upper limit (within pre-trigger | |
| 636 region) for background calculation. In our example, if we want to | |
| 637 calculate the background between 30000 and 50000 meters for all | |
| 638 photoncounting channels and we want to use the first 500 pre-trigger | |
| 639 bins for the background calculation for the 1064nm channel we have to | |
| 640 set: | |
| 641 | |
| 642 :: | |
| 643 | |
| 644 Background_High = 500, 50000, 50000, 50000 ; | |
| 645 | |
| 646 Molecular_Calc | |
| 647 This mandatory variable defines the way used by SCC to calculate the | |
| 648 molecular density profile. At the moment two options are available: | |
| 649 | |
| 650 #. US Standard Atmosphere 1976. In this case the value of this | |
| 651 variable has to be 0 | |
| 652 | |
| 653 #. Radiosounding. In this case the value of this variable has to be 1 | |
| 654 | |
| 655 If we decide to use the option 1. we have to provide also the | |
| 656 measured pressure and temperature at lidar station level. Indeed if | |
| 657 we decide to use the option 2. a radiosounding file has to be | |
| 658 submitted separately in NetCDF format (the structure of this file is | |
| 659 summarized in table tab:sounding). Let’s suppose we want to use the | |
| 660 option 1. so: | |
| 661 | |
| 662 :: | |
| 663 | |
| 664 Molecular_Calc = 0 ; | |
| 665 | |
| 666 Pressure_at_Lidar_Station | |
| 667 Because we have chosen the US Standard Atmosphere for calculation of | |
| 668 the molecular density profile we have to give the pressure in hPa at | |
| 669 lidar station level: | |
| 670 | |
| 671 :: | |
| 672 | |
| 673 Pressure_at_Lidar_Station = 1010 ; | |
| 674 | |
| 675 Temperature_at_Lidar_Station | |
| 676 Because we have chosen the US Standard Atmosphere for calculation of | |
| 677 the molecular density profile we have to give the temperature in C at | |
| 678 lidar station level: | |
| 679 | |
| 680 :: | |
| 681 | |
| 682 Temperature_at_Lidar_Station = 19.8 ; | |
| 683 | |
| 684 Depolarization_Factor(channels) | |
| 685 This array is required only for lidar systems that use the two | |
| 686 depolarization channels for the backscatter retrieval. It represents | |
| 687 the factor :math:`f` to calculate the total backscatter signal | |
| 688 :math:`S_t` combining its cross :math:`S_c` and parallel | |
| 689 :math:`S_p` components: :math:`S_t=S_p+fS_c`. This factor is | |
| 690 mandatory only for systems acquiring :math:`S_c` and :math:`S_p` | |
| 691 and not :math:`S_t`. For systems acquiring :math:`S_c`, | |
| 692 :math:`S_p` and :math:`S_t` this factor is optional and it will | |
| 693 be used only for depolarizaton ratio calculation. Moreover only the | |
| 694 values of the array corresponding to cross polarization channels will | |
| 695 be considered; all other values will be not taken into account and | |
| 696 should be set to undefined value. In our example for the wavelength | |
| 697 532nm we have only the cross and the parallel components and not the | |
| 698 total one. So we have to give the value of this factor only in | |
| 699 correspondence of the 532nm cross polarization channel that | |
| 700 corresponds to the channel index 1. Suppose that this factor is 0.88. | |
| 701 Moreover, because we don’t have any other depolarization channels we | |
| 702 have also to set all other values of the array to undefined value. | |
| 703 | |
| 704 :: | |
| 705 | |
| 706 Depolarization_Factor = _,0.88,_,_ ; | |
| 707 | |
| 708 LR_Input(channels) | |
| 709 This array is required only for lidar channels for which elastic | |
| 710 backscatter retrieval has to be performed. It defines the lidar ratio | |
| 711 to be used within this retrieval. Two options are available: | |
| 712 | |
| 713 #. The user can submit a lidar ratio profile. In this case the value | |
| 714 of this variable has to be 0. | |
| 715 | |
| 716 #. A fixed value of lidar ratio can be used. In this case the value | |
| 717 of this variable has to be 1. | |
| 718 | |
| 719 If we decide to use the option 1. a lidar ratio file has to be | |
| 720 submitted separately in NetCDF format (the structure of this file is | |
| 721 summarized in table tab:lr). If we decide to use the option 2. the | |
| 722 fixed value of lidar ratio will be taken from SCC\_DB. In our example | |
| 723 we have to give a value of this array only for the 1064nm lidar | |
| 724 channel because for the 532nm we will be able to retrieve a Raman | |
| 725 backscatter coefficient. In case we want to use the fixed value | |
| 726 stored in SCC\_DB we have to set: | |
| 727 | |
| 728 :: | |
| 729 | |
| 730 LR_Input = 1,_,_,_ ; | |
| 731 | |
| 732 DAQ_Range(channels) | |
| 733 This array is required only if one or more lidar signals are | |
| 734 acquired in analog mode. It gives the analog scale in mV used to | |
| 735 acquire the analog signals. In our example we have only the 1064nm | |
| 736 channel acquired in analog mode. If we have used a 100mV analog scale | |
| 737 to acquire this channel we have to set: | |
| 738 | |
| 739 :: | |
| 740 | |
| 741 DAQ_Range = 100,_,_,_ ; | |
| 742 | |
| 743 Global attributes | |
| 744 ~~~~~~~~~~~~~~~~~ | |
| 745 | |
| 746 Measurement_ID | |
| 747 This mandatory global attribute defines the measurement ID | |
| 748 corresponding to the actual lidar measurement. It is a string | |
| 749 composed by 12 characters. The first 8 characters give the start date | |
| 750 of measurement in the format YYYYMMDD. The next 2 characters give the | |
| 751 Earlinet call-sign of the station. The last 2 characters are used to | |
| 752 distinguish between different time-series within the same date. In | |
| 753 our example we have to set: | |
| 754 | |
| 755 :: | |
| 756 | |
| 757 Measurement_ID= "20090130cc00" ; | |
| 758 | |
| 759 RawData_Start_Date | |
| 760 This mandatory global attribute defines the start date of lidar | |
| 761 measurements in the format YYYYMMDD. In our case we have: | |
| 762 | |
| 763 :: | |
| 764 | |
| 765 RawData_Start_Date = "20090130" ; | |
| 766 | |
| 767 RawData_Start_Time_UT | |
| 768 This mandatory global attribute defines the UT start time of lidar | |
| 769 measurements in the format HHMMSS. In our case we have: | |
| 770 | |
| 771 :: | |
| 772 | |
| 773 RawData_Start_Time_UT = "000001" ; | |
| 774 | |
| 775 RawData_Stop_Time_UT`` | |
| 776 This mandatory global attribute defines the UT stop time of lidar | |
| 777 measurements in the format HHMMSS. In our case we have: | |
| 778 | |
| 779 :: | |
| 780 | |
| 781 RawData_Stop_Time_UT = "000501" ; | |
| 782 | |
| 783 RawBck_Start_Date | |
| 784 This optional global attribute defines the start date of dark | |
| 785 measurements in the format YYYYMMDD. In our case we have: | |
| 786 | |
| 787 :: | |
| 788 | |
| 789 RawBck_Start_Date = "20090129" ; | |
| 790 | |
| 791 RawBck_Start_Time_UT | |
| 792 This optional global attribute defines the UT start time of dark | |
| 793 measurements in the format HHMMSS. In our case we have: | |
| 794 | |
| 795 :: | |
| 796 | |
| 797 RawBck_Start_Time_UT = "235001" ; | |
| 798 | |
| 799 RawBck_Stop_Time_UT | |
| 800 This optional global attribute defines the UT stop time of dark | |
| 801 measurements in the format HHMMSS. In our case we have: | |
| 802 | |
| 803 :: | |
| 804 | |
| 805 RawBck_Stop_Time_UT = "235301" ; | |
| 806 | |
| 807 Example of file (CDL format) | |
| 808 ---------------------------- | |
| 809 | |
| 810 To summarize we have the following NetCDF Raw Lidar Data file (in CDL | |
| 811 format): | |
| 812 | |
| 813 :: | |
| 814 | |
| 815 dimensions: | |
| 816 points = 5000 ; | |
| 817 channels = 4 ; | |
| 818 time = UNLIMITED ; // (10 currently) | |
| 819 nb_of_time_scales = 2 ; | |
| 820 scan_angles = 1 ; | |
| 821 time_bck = 6 ; | |
| 822 variables: | |
| 823 int channel_ID(channels) ; | |
| 824 int Laser_Repetition_Rate(channels) ; | |
| 825 double Laser_Pointing_Angle(scan_angles) ; | |
| 826 int ID_Range(channels) ; | |
| 827 int Scattering_Mechanism(channels) ; | |
| 828 double Emitted_Wavelength(channels) ; | |
| 829 double Detected_Wavelength(channels) ; | |
| 830 double Raw_Data_Range_Resolution(channels) ; | |
| 831 int Background_Mode(channels) ; | |
| 832 double Background_Low(channels) ; | |
| 833 double Background_High(channels) ; | |
| 834 int Molecular_Calc ; | |
| 835 double Pressure_at_Lidar_Station ; | |
| 836 double Temperature_at_Lidar_Station ; | |
| 837 int id_timescale(channels) ; | |
| 838 double Dead_Time(channels) ; | |
| 839 int Dead_Time_Corr_Type(channels) ; | |
| 840 int Acquisition_Mode(channels) ; | |
| 841 double Trigger_Delay(channels) ; | |
| 842 int LR_Input(channels) ; | |
| 843 int Laser_Pointing_Angle_of_Profiles(time, nb_of_time_scales) ; | |
| 844 int Raw_Data_Start_Time(time, nb_of_time_scales) ; | |
| 845 int Raw_Data_Stop_Time(time, nb_of_time_scales) ; | |
| 846 int Raw_Bck_Start_Time(time_bck, nb_of_time_scales) ; | |
| 847 int Raw_Bck_Stop_Time(time_bck, nb_of_time_scales) ; | |
| 848 int Laser_Shots(time, channels) ; | |
| 849 double Raw_Lidar_Data(time, channels, points) ; | |
| 850 double Background_Profile(time_bck, channels, points) ; | |
| 851 double DAQ_Range(channels) ; | |
| 852 | |
| 853 // global attributes: | |
| 854 :Measurement_ID = "20090130cc00" ; | |
| 855 :RawData_Start_Date = "20090130" ; | |
| 856 :RawData_Start_Time_UT = "000001" ; | |
| 857 :RawData_Stop_Time_UT = "000501" ; | |
| 858 :RawBck_Start_Date = "20090129" ; | |
| 859 :RawBck_Start_Time_UT = "235001" ; | |
| 860 :RawBck_Stop_Time_UT = "235301" ; | |
| 861 | |
| 862 data: | |
| 863 | |
| 864 channel_ID = 7, 5, 6, 8 ; | |
| 865 | |
| 866 Laser_Repetition_Rate = 50, 50, 50, 50 ; | |
| 867 | |
| 868 Laser_Pointing_Angle = 5 ; | |
| 869 | |
| 870 ID_Range = 1, 1, 1, 1 ; | |
| 871 | |
| 872 Scattering_Mechanism = 0, 2, 3, 1 ; | |
| 873 | |
| 874 Emitted_Wavelength = 1064, 532, 532, 532 ; | |
| 875 | |
| 876 Detected_Wavelength = 1064, 532, 532, 607 ; | |
| 877 | |
| 878 Raw_Data_Range_Resolution = 7.5, 15, 15, 15 ; | |
| 879 | |
| 880 Background_Mode = 0, 1, 1, 1 ; | |
| 881 | |
| 882 Background_Low = 0, 30000, 30000, 30000 ; | |
| 883 | |
| 884 Background_High = 500, 50000, 50000, 50000 ; | |
| 885 | |
| 886 Molecular_Calc = 0 ; | |
| 887 | |
| 888 Pressure_at_Lidar_Station = 1010 ; | |
| 889 | |
| 890 Temperature_at_Lidar_Station = 19.8 ; | |
| 891 | |
| 892 id_timescale = 1, 0, 0, 0 ; | |
| 893 | |
| 894 Dead_Time = _, 10, 10, 10 ; | |
| 895 | |
| 896 Dead_Time_Corr_Type = _, 0, 0, 0 ; | |
| 897 | |
| 898 Acquisition_Mode = 0, 1, 1, 1 ; | |
| 899 | |
| 900 Trigger_Delay = 50, 0, 0, 0 ; | |
| 901 | |
| 902 LR_Input = 1,_,_,_ ; | |
| 903 | |
| 904 DAQ_Range = 100,_,_,_ ; | |
| 905 | |
| 906 Laser_Pointing_Angle_of_Profiles = | |
| 907 0, 0, | |
| 908 0, 0, | |
| 909 0, 0, | |
| 910 0, 0, | |
| 911 0, 0, | |
| 912 _, 0, | |
| 913 _, 0, | |
| 914 _, 0, | |
| 915 _, 0, | |
| 916 _, 0 ; | |
| 917 | |
| 918 | |
| 919 Raw_Data_Start_Time = | |
| 920 0, 0, | |
| 921 60, 30, | |
| 922 120, 60, | |
| 923 180, 90, | |
| 924 240, 120, | |
| 925 _, 150, | |
| 926 _, 180, | |
| 927 _, 210, | |
| 928 _, 240, | |
| 929 _, 270 ; | |
| 930 | |
| 931 Raw_Data_Stop_Time = | |
| 932 60, 30, | |
| 933 120, 60, | |
| 934 180, 90, | |
| 935 240, 120, | |
| 936 300, 150, | |
| 937 _, 180, | |
| 938 _, 210, | |
| 939 _, 240, | |
| 940 _, 270, | |
| 941 _, 300 ; | |
| 942 | |
| 943 | |
| 944 Raw_Bck_Start_Time = | |
| 945 0, 0, | |
| 946 60, 30, | |
| 947 120, 60, | |
| 948 _, 90, | |
| 949 _, 120, | |
| 950 _, 150; | |
| 951 | |
| 952 | |
| 953 Raw_Bck_Stop_Time = | |
| 954 60, 30, | |
| 955 120, 60, | |
| 956 180, 90, | |
| 957 _, 120, | |
| 958 _, 150, | |
| 959 _, 180 ; | |
| 960 | |
| 961 | |
| 962 Laser_Shots = | |
| 963 1500, 3000, 3000, 3000, | |
| 964 1500, 3000, 3000, 3000, | |
| 965 1500, 3000, 3000, 3000, | |
| 966 1500, 3000, 3000, 3000, | |
| 967 1500, 3000, 3000, 3000, | |
| 968 1500, _, _, _, | |
| 969 1500, _, _, _, | |
| 970 1500, _, _, _, | |
| 971 1500, _, _, _, | |
| 972 1500, _, _, _ ; | |
| 973 | |
| 974 | |
| 975 Raw_Lidar_Data = ... | |
| 976 | |
| 977 Background_Profile = ... | |
| 978 | |
| 979 Please keep in mind that in case you submit a file like the previous one | |
| 980 all the parameters present in it will be used by the SCC even if you | |
| 981 have different values for the same parameters within the SCC\_DB. If you | |
| 982 want to use the values already stored in SCC\_DB (this should be the | |
| 983 usual way to use SCC) the Raw Lidar Data input file has to be | |
| 984 modified as follows: | |
| 985 | |
| 986 :: | |
| 987 | |
| 988 dimensions: | |
| 989 points = 5000 ; | |
| 990 channels = 4 ; | |
| 991 time = UNLIMITED ; // (10 currently) | |
| 992 nb_of_time_scales = 2 ; | |
| 993 scan_angles = 1 ; | |
| 994 time_bck = 6 ; | |
| 995 variables: | |
| 996 int channel_ID(channels) ; | |
| 997 double Laser_Pointing_Angle(scan_angles) ; | |
| 998 double Background_Low(channels) ; | |
| 999 double Background_High(channels) ; | |
| 1000 int Molecular_Calc ; | |
| 1001 double Pressure_at_Lidar_Station ; | |
| 1002 double Temperature_at_Lidar_Station ; | |
| 1003 int id_timescale(channels) ; | |
| 1004 int Laser_Pointing_Angle_of_Profiles(time, nb_of_time_scales) ; | |
| 1005 int Raw_Data_Start_Time(time, nb_of_time_scales) ; | |
| 1006 int Raw_Data_Stop_Time(time, nb_of_time_scales) ; | |
| 1007 int Raw_Bck_Start_Time(time_bck, nb_of_time_scales) ; | |
| 1008 int Raw_Bck_Stop_Time(time_bck, nb_of_time_scales) ; | |
| 1009 int LR_Input(channels) ; | |
| 1010 int Laser_Shots(time, channels) ; | |
| 1011 double Raw_Lidar_Data(time, channels, points) ; | |
| 1012 double Background_Profile(time_bck, channels, points) ; | |
| 1013 double DAQ_Range(channels) ; | |
| 1014 | |
| 1015 // global attributes: | |
| 1016 :Measurement_ID = "20090130cc00" ; | |
| 1017 :RawData_Start_Date = "20090130" ; | |
| 1018 :RawData_Start_Time_UT = "000001" ; | |
| 1019 :RawData_Stop_Time_UT = "000501" ; | |
| 1020 :RawBck_Start_Date = "20090129" ; | |
| 1021 :RawBck_Start_Time_UT = "235001" ; | |
| 1022 :RawBck_Stop_Time_UT = "235301" ; | |
| 1023 | |
| 1024 data: | |
| 1025 | |
| 1026 channel_ID = 7, 5, 6, 8 ; | |
| 1027 | |
| 1028 Laser_Pointing_Angle = 5 ; | |
| 1029 | |
| 1030 Background_Low = 0, 30000, 30000, 30000 ; | |
| 1031 | |
| 1032 Background_High = 500, 50000, 50000, 50000 ; | |
| 1033 | |
| 1034 Molecular_Calc = 0 ; | |
| 1035 | |
| 1036 Pressure_at_Lidar_Station = 1010 ; | |
| 1037 | |
| 1038 Temperature_at_Lidar_Station = 19.8 ; | |
| 1039 | |
| 1040 id_timescale = 1, 0, 0, 0 ; | |
| 1041 | |
| 1042 LR_Input = 1,_,_,_ ; | |
| 1043 | |
| 1044 DAQ_Range = 100,_,_,_ ; | |
| 1045 | |
| 1046 Laser_Pointing_Angle_of_Profiles = | |
| 1047 0, 0, | |
| 1048 0, 0, | |
| 1049 0, 0, | |
| 1050 0, 0, | |
| 1051 0, 0, | |
| 1052 _, 0, | |
| 1053 _, 0, | |
| 1054 _, 0, | |
| 1055 _, 0, | |
| 1056 _, 0 ; | |
| 1057 | |
| 1058 | |
| 1059 Raw_Data_Start_Time = | |
| 1060 0, 0, | |
| 1061 60, 30, | |
| 1062 120, 60, | |
| 1063 180, 90, | |
| 1064 240, 120, | |
| 1065 _, 150, | |
| 1066 _, 180, | |
| 1067 _, 210, | |
| 1068 _, 240, | |
| 1069 _, 270 ; | |
| 1070 | |
| 1071 Raw_Data_Stop_Time = | |
| 1072 60, 30, | |
| 1073 120, 60, | |
| 1074 180, 90, | |
| 1075 240, 120, | |
| 1076 300, 150, | |
| 1077 _, 180, | |
| 1078 _, 210, | |
| 1079 _, 240, | |
| 1080 _, 270, | |
| 1081 _, 300 ; | |
| 1082 | |
| 1083 | |
| 1084 Raw_Bck_Start_Time = | |
| 1085 0, 0, | |
| 1086 60, 30, | |
| 1087 120, 60, | |
| 1088 _, 90, | |
| 1089 _, 120, | |
| 1090 _, 150; | |
| 1091 | |
| 1092 | |
| 1093 Raw_Bck_Stop_Time = | |
| 1094 60, 30, | |
| 1095 120, 60, | |
| 1096 180, 90, | |
| 1097 _, 120, | |
| 1098 _, 150, | |
| 1099 _, 180 ; | |
| 1100 | |
| 1101 | |
| 1102 Laser_Shots = | |
| 1103 1500, 3000, 3000, 3000, | |
| 1104 1500, 3000, 3000, 3000, | |
| 1105 1500, 3000, 3000, 3000, | |
| 1106 1500, 3000, 3000, 3000, | |
| 1107 1500, 3000, 3000, 3000, | |
| 1108 1500, _, _, _, | |
| 1109 1500, _, _, _, | |
| 1110 1500, _, _, _, | |
| 1111 1500, _, _, _, | |
| 1112 1500, _, _, _ ; | |
| 1113 | |
| 1114 | |
| 1115 Raw_Lidar_Data = ... | |
| 1116 | |
| 1117 Background_Profile = ... | |
| 1118 | |
| 1119 This example file contains the minimum collection of mandatory | |
| 1120 information that has to be found within the Raw Lidar Data input | |
| 1121 file. If it is really necessary, the user can decide to add to these | |
| 1122 mandatory parameters any number of additional parameters considered in | |
| 1123 the previous example. | |
| 1124 | |
| 1125 Finally, suppose we want to make the following changes with respect to | |
| 1126 the previous example: | |
| 1127 | |
| 1128 #. use a sounding file for molecular density calculation instead of “US | |
| 1129 Standar Atmosphere 1976” | |
| 1130 | |
| 1131 #. supply a lidar ratio profile to use in elastic backscatter retrieval | |
| 1132 instead of a fixed value | |
| 1133 | |
| 1134 #. provide a overlap function for overlap correction | |
| 1135 | |
| 1136 In this case we have to generate the following NetCDF additional files: | |
| 1137 | |
| 1138 rs_20090130cc00.nc | |
| 1139 The name of Sounding Data file has to be computed as follows: | |
| 1140 ``"rs_"``+``Measurement_ID`` | |
| 1141 The structure of this file is summarized in table tab:sounding. | |
| 1142 | |
| 1143 ov_20090130cc00.nc | |
| 1144 The name of Overlap file has to be computed as follows: | |
| 1145 ``"ov_"``+``Measurement_ID`` | |
| 1146 The structure of this file is summarized in table tab:overlap. | |
| 1147 | |
| 1148 lr_20090130cc00.nc | |
| 1149 The name of Lidar Ratio file has to be computed as follows: | |
| 1150 ``"lr_"``+``Measurement_ID`` | |
| 1151 The structure of this file is summarized in table tab:lr. | |
| 1152 | |
| 1153 Moreover we need to apply the following changes to the Raw Lidar Data | |
| 1154 input file: | |
| 1155 | |
| 1156 1. Change the value of the variable ``Molecular_Calc`` as follows: | |
| 1157 | |
| 1158 :: | |
| 1159 | |
| 1160 Molecular_Calc = 1 ; | |
| 1161 | |
| 1162 Of course the variables ``Pressure_at_Lidar_Station`` and | |
| 1163 ``Temperature_at_Lidar_Station`` are not necessary anymore. | |
| 1164 | |
| 1165 2. Change the values of the array ``LR_Input`` as follows: | |
| 1166 | |
| 1167 :: | |
| 1168 | |
| 1169 LR_Input = 0,_,_,_ ; | |
| 1170 | |
| 1171 3. Add the global attribute ``Sounding_File_Name`` | |
| 1172 | |
| 1173 :: | |
| 1174 | |
| 1175 Sounding_File_Name = "rs_20090130cc00.nc" ; | |
| 1176 | |
| 1177 5. Add the global attribute ``LR_File_Name`` | |
| 1178 | |
| 1179 :: | |
| 1180 | |
| 1181 LR_File_Name = "lr_20090130cc00.nc" ; | |
| 1182 | |
| 1183 6. Add the global attribute ``Overlap_File_Name`` | |
| 1184 | |
| 1185 :: | |
| 1186 | |
| 1187 Overlap_File_Name = "ov_20090130cc00.nc" ; |
