ATMS 360 Homework (return to main page)
Table of values of the Rayleigh Scattering Optical Depth for the whole atmosphere, and Reno's nominal pressure.
Calculations were made with this spreadsheet.
An alternative approach is described here.
On an exceptionally clear day with no particles in the atmosphere, and no gaseous absorption,
these optical depth values are what you would expect to find for the slope in the Langley plot
of air mass versus the natural logarithm the voltage measured with the sun photometer.

Wavelength (nm)
Rayleigh_Scattering_Optical_Depth_for_The_Atmos_Reno(Pressure=850mb)
250
2.267281269
252
2.188241945
254
2.112706778
256
2.040485605
258
1.971400586
260
1.905285271
262
1.841983739
264
1.78134982
266
1.723246377
268
1.667544657
270
1.61412369
272
1.562869739
274
1.513675798
276
1.466441126
278
1.421070818
280
1.377475417
282
1.335570544
284
1.295276569
286
1.256518296
288
1.219224678
290
1.183328552
292
1.148766395
294
1.115478088
296
1.083406715
298
1.052498356
300
1.022701911
302
0.993968926
304
0.966253436
306
0.939511818
308
0.913702649
310
0.888786584
312
0.864726232
314
0.841486042
316
0.819032205
318
0.797332547
320
0.776356447
322
0.756074742
324
0.736459654
326
0.717484709
328
0.69912467
330
0.681355468
332
0.664154141
334
0.647498775
336
0.631368451
338
0.615743189
340
0.600603901
342
0.585932349
344
0.571711094
346
0.557923464
348
0.544553509
350
0.531585967
352
0.519006232
354
0.506800318
356
0.49495483
358
0.483456939
360
0.472294347
362
0.46145527
364
0.450928407
366
0.440702919
368
0.430768412
370
0.421114907
372
0.411732829
374
0.402612985
376
0.393746545
378
0.38512503
380
0.37674029
382
0.368584495
384
0.360650119
386
0.352929921
388
0.345416943
390
0.338104489
392
0.330986114
394
0.32405562
396
0.317307038
398
0.310734621
400
0.304332834
402
0.298096348
404
0.292020026
406
0.286098918
408
0.280328256
410
0.274703439
412
0.269220035
414
0.263873765
416
0.258660505
418
0.253576274
420
0.248617231
422
0.24377967
424
0.239060012
426
0.2344548
428
0.229960698
430
0.225574482
432
0.221293039
434
0.217113358
436
0.213032533
438
0.209047753
440
0.2051563
442
0.201355546
444
0.19764295
446
0.194016056
448
0.190472484
450
0.187009934
452
0.183626179
454
0.180319066
456
0.177086507
458
0.173926482
460
0.170837037
462
0.167816276
464
0.164862366
466
0.161973527
468
0.159148039
470
0.156384232
472
0.153680488
474
0.151035239
476
0.148446964
478
0.145914191
480
0.143435488
482
0.141009469
484
0.13863479
486
0.136310145
488
0.134034268
490
0.131805929
492
0.129623938
494
0.127487135
496
0.125394397
498
0.123344632
500
0.121336782
502
0.119369815
504
0.117442733
506
0.115554565
508
0.113704367
510
0.111891222
512
0.110114239
514
0.108372553
516
0.10666532
518
0.104991724
520
0.103350967
522
0.101742277
524
0.100164902
526
0.098618109
528
0.097101186
530
0.095613441
532
0.0941542
534
0.092722808
536
0.091318627
538
0.089941035
540
0.088589429
542
0.087263219
544
0.085961834
546
0.084684714
548
0.083431318
550
0.082201116
552
0.080993593
554
0.079808247
556
0.07864459
558
0.077502144
560
0.076380447
562
0.075279045
564
0.074197499
566
0.073135377
568
0.072092263
570
0.071067747
572
0.070061431
574
0.069072928
576
0.06810186
578
0.067147856
580
0.066210558
582
0.065289613
584
0.064384681
586
0.063495427
588
0.062621524
590
0.061762655
592
0.060918509
594
0.060088784
596
0.059273184
598
0.058471421
600
0.057683212
602
0.056908284
604
0.056146366
606
0.055397198
608
0.054660523
610
0.053936092
612
0.05322366
614
0.052522988
616
0.051833844
618
0.051156001
620
0.050489235
622
0.049833331
624
0.049188074
626
0.048553259
628
0.047928682
630
0.047314146
632
0.046709456
634
0.046114424
636
0.045528864
638
0.044952595
640
0.044385441
642
0.043827229
644
0.043277789
646
0.042736956
648
0.042204569
650
0.041680469
652
0.041164501
654
0.040656515
656
0.040156361
658
0.039663896
660
0.039178977
662
0.038701466
664
0.038231226
666
0.037768126
668
0.037312034
670
0.036862825
672
0.036420373
674
0.035984556
676
0.035555255
678
0.035132353
680
0.034715736
682
0.034305291
684
0.03390091
686
0.033502484
688
0.033109908
690
0.03272308
692
0.032341898
694
0.031966264
696
0.031596081
698
0.031231253
700
0.030871688
702
0.030517295
704
0.030167985
706
0.02982367
708
0.029484265
710
0.029149685
712
0.028819848
714
0.028494674
716
0.028174084
718
0.027857999
720
0.027546345
722
0.027239047
724
0.026936031
726
0.026637226
728
0.026342562
730
0.02605197
732
0.025765383
734
0.025482735
736
0.025203959
738
0.024928994
740
0.024657776
742
0.024390244
744
0.024126338
746
0.023865999
748
0.02360917
750
0.023355793
752
0.023105813
754
0.022859175
756
0.022615826
758
0.022375713
760
0.022138785
762
0.021904991
764
0.02167428
766
0.021446605
768
0.021221918
770
0.021000171
772
0.020781318
774
0.020565315
776
0.020352115
778
0.020141677
780
0.019933957
782
0.019728913
784
0.019526503
786
0.019326687
788
0.019129425
790
0.018934678
792
0.018742408
794
0.018552577
796
0.018365147
798
0.018180082
800
0.017997347
802
0.017816906
804
0.017638725
806
0.017462769
808
0.017289006
810
0.017117403
812
0.016947927
814
0.016780547
816
0.016615232
818
0.016451951
820
0.016290674
822
0.016131372
824
0.015974016
826
0.015818577
828
0.015665028
830
0.01551334
832
0.015363486
834
0.015215441
836
0.015069178
838
0.01492467
840
0.014781894
842
0.014640823
844
0.014501435
846
0.014363703
848
0.014227606
850
0.014093119
852
0.01396022
854
0.013828886
856
0.013699096
858
0.013570827
860
0.013444058
862
0.013318768
864
0.013194937
866
0.013072544
868
0.012951568
870
0.012831991
872
0.012713793
874
0.012596954
876
0.012481457
878
0.012367282
880
0.012254412
882
0.012142829
884
0.012032514
886
0.011923451
888
0.011815623
890
0.011709012
892
0.011603604
894
0.01149938
896
0.011396325
898
0.011294424
900
0.011193661
902
0.011094021
904
0.010995489
906
0.010898049
908
0.010801688
910
0.010706391
912
0.010612145
914
0.010518934
916
0.010426746
918
0.010335567
920
0.010245384
922
0.010156183
924
0.010067953
926
0.00998068
928
0.009894352
930
0.009808956
932
0.009724481
934
0.009640914
936
0.009558245
938
0.00947646
940
0.00939555
942
0.009315502
944
0.009236307
946
0.009157952
948
0.009080427
950
0.009003722
952
0.008927826
954
0.008852729
956
0.008778422
958
0.008704893
960
0.008632133
962
0.008560133
964
0.008488883
966
0.008418373
968
0.008348595
970
0.00827954
972
0.008211197
974
0.00814356
976
0.008076618
978
0.008010363
980
0.007944787
982
0.007879882
984
0.007815639
986
0.00775205
988
0.007689107
990
0.007626802
992
0.007565128
994
0.007504077
996
0.007443641
998
0.007383813
1000
0.007324586
1002
0.007265952
1004
0.007207904
1006
0.007150435
1008
0.007093539
1010
0.007037208
1012
0.006981435
1014
0.006926215
1016
0.00687154
1018
0.006817404
1020
0.006763801
1022
0.006710724
1024
0.006658168
1026
0.006606125
1028
0.006554591
1030
0.006503558
1032
0.006453022
1034
0.006402976
1036
0.006353415
1038
0.006304333
1040
0.006255725
1042
0.006207584
1044
0.006159907
1046
0.006112686
1048
0.006065918