|
<br />parameters and observing the changes in the calculated
<br />values of N*. Given the value of N* for the optimal
<br />group of a given size, how different is the corres-
<br />ponding value for the next best grouping, etc. Tables
<br />5 and 6 show that many combinations will actually give
<br />a value of N* close to the optimal.
<br />
<br />How sensitive is N* to the values of the weight
<br />coefficients ai? The best 10 ranking groups of size
<br />
<br />6 were used for the sensitivity test.
<br />
<br />The procedure was to modify 2 weight factors (those
<br />corresponding to the first 2 columns of Table 7) by
<br />1, 5 and 10%, keeping these fixed and recalculating
<br />
<br />the remaining 4ai according to the optimization pro-
<br />
<br />cedure. The results are shown in Table 7. They indi-
<br />cate that the weight factors can be rounded off without
<br />appreciable effects.
<br />
<br />How sensitive is N* to the runoff data? The opti-
<br />mal group of size 6 in the Upper Basin of the Colorado
<br />was used for this test. It is a test of sensitivity
<br />of N* to the sample covariance matrix. The procedure
<br />was to select at random 7 years from the total record
<br />(1948-1964). The years turned out to be: 1948, 1951,
<br />1954, 1956, 1958, 1960 and 1963. Then runoff data for
<br />3 out of the 7 years were deleted from the entire
<br />record. This can be done in 35 ways. For each sample
<br />N* was calculated. Table 8 shows the results.
<br />
<br />TABLE 2(a) STATION CHARACTERISTICS - THE SAN JUAN MOUNTAINS
<br />
<br />CSU ID
<br />(U.S.G.S,
<br />No. )
<br />
<br />1073080
<br />(9.36550)
<br />1073420
<br />(9.3630)
<br />1073448
<br />(9.36100)
<br />1073460
<br />(9,35950)
<br />1075830
<br />(9.35350)
<br />1076420
<br />(9.34950)
<br />1077015
<br />(9.34600)
<br />1077200
<br />(9.34350)
<br />1077250
<br />(9.34300)
<br />1077400
<br />(9.34250)
<br />1272440
<br />(9.17300)
<br />1272445
<br />(9.17250)
<br />1278800
<br />(9.16500)
<br />1371530
<br />(9.14700)
<br />1371555
<br />(9.14620)
<br />
<br />Name
<br />
<br />La Plata River
<br />at Hesperus
<br />Florida River
<br />near Durango
<br />Hermosa Creek
<br />near Hermosa
<br />Animas River
<br />above Tacoma
<br />Los pinos River
<br />near Bayfield
<br />Piedra River
<br />near Piedra
<br />Navajo River
<br />at Edith
<br />Ri to Blanco near
<br />Pagosa Springs
<br />Rio Blanco near
<br />Pagosa Springs
<br />San Juan River
<br />at Pagosa Springs
<br />Beaver Creek
<br />near Norwood
<br />San Miguel Creek
<br />near Placerville
<br />Dolores River
<br />below Rico
<br />Dallas Creek
<br />near Ridgway
<br />Uncompahgre River
<br />near Ridgl'o"ay
<br />
<br />Location
<br />Latitude
<br />Longi tude
<br />
<br />37 17 20
<br />108 2 5
<br />37 19 40
<br />107 44 40
<br />37 25 30
<br />107 50 20
<br />37 34 10
<br />107 46 40
<br />37 23 0
<br />107 34 30
<br />37 14 0
<br />107 20 30
<br />37 0 10
<br />106 54 25
<br />37 11 40
<br />106 54 20
<br />37 12 46
<br />106 47 38
<br />37 15 50
<br />107 0 40
<br />37 58 0
<br />108 II 0
<br />38 2 5
<br />108 7 15
<br />37 38 25
<br />108 3 5
<br />38 10 50
<br />107 45 40
<br />38 II 5
<br />107 44 40
<br />
<br />Elevation
<br />feet
<br />
<br />Drainage
<br />Area
<br />mile2
<br />
<br />8105
<br />
<br />7302
<br />
<br />6706
<br />
<br />172,0
<br />
<br />37,0
<br />
<br />96.0
<br />
<br />23,3
<br />
<br />58. {)
<br />
<br />35,2
<br />
<br />96.2
<br />
<br />Recording
<br />Length
<br />
<br />Continuous
<br />Recording
<br />Length
<br />
<br />Mean (inch)
<br />& variance
<br />(inch2)
<br />Annual Spring
<br />
<br />16.70
<br />45.03
<br />15,13
<br />46.03
<br />10,95
<br />28.25
<br />20,66
<br />45,12
<br />18,55
<br />37.46
<br />11. 46
<br />31.16
<br />12.46
<br />24,65
<br />10.74
<br />35,33
<br />19,65
<br />59.20
<br />16.83
<br />51. 86
<br />6,55
<br />35.73
<br />10,06
<br />9.66
<br />16.44
<br />46.04
<br />5.47
<br />4,74
<br />13.49
<br />3,09
<br />
<br />Ratio of
<br />spring to
<br />annual
<br />runoff
<br />
<br />13,50
<br />42.81
<br />12,21
<br />27.39
<br />8.91
<br />17,53
<br />15,91
<br />39,95
<br />12.47
<br />30.ll
<br />9,02
<br />18,71
<br />9,37
<br />13,70
<br />9.43
<br />19.81
<br />15.39
<br />46.42
<br />13,66
<br />38,54
<br />5.46
<br />17,89
<br />7.39
<br />8,49
<br />13,57
<br />14,39
<br />2.94
<br />2,41
<br />9,19
<br />4.10
<br />
<br />Increase
<br />in
<br />runoff
<br />(inch)
<br />
<br />.81
<br />
<br />.81
<br />
<br />.81
<br />
<br />.77
<br />
<br />.67
<br />
<br />.79
<br />
<br />,75
<br />
<br />,88
<br />
<br />,78
<br />
<br />,81
<br />
<br />.83
<br />
<br />.73
<br />
<br />,83
<br />
<br />.54
<br />
<br />.68
<br />
<br />Number of
<br />Percentage years for
<br />Increase Evaluation
<br />
<br />1.15
<br />
<br />8.5
<br />
<br />124
<br />
<br />7520
<br />
<br />348,0
<br />
<br />1904-64
<br />
<br />1917-64
<br />
<br />1.00
<br />
<br />8.2
<br />
<br />105
<br />
<br />7515
<br />
<br />284,0
<br />
<br />1899-60
<br />
<br />1927-60
<br />
<br />,98
<br />
<br />11. 0
<br />
<br />70
<br />
<br />6530
<br />
<br />371. 0
<br />
<br />1912-64
<br />
<br />1940-64
<br />
<br />1.50
<br />
<br />9.4
<br />
<br />68
<br />
<br />7033
<br />
<br />172,0
<br />
<br />1946-56
<br />
<br />1946-56
<br />
<br />1.01
<br />
<br />ll3
<br />
<br />7330
<br />
<br />7950
<br />
<br />7052
<br />
<br />298.0
<br />
<br />1928-64
<br />
<br />1928-64
<br />
<br />8.1
<br />9.7
<br />
<br />93
<br />
<br />8008
<br />7096
<br />
<br />308,0
<br />
<br />1912-64
<br />
<br />1939-64
<br />
<br />.88
<br />
<br />,94
<br />
<br />10.0
<br />
<br />60
<br />
<br />8422
<br />
<br />105.0
<br />
<br />1913-64
<br />
<br />1913-64
<br />
<br />1.02
<br />
<br />11.8
<br />
<br />73
<br />
<br />6980
<br />
<br />6878
<br />
<br />150.0
<br />
<br />1935-52
<br />
<br />1935-52
<br />
<br />1. 31
<br />
<br />8,5
<br />
<br />104
<br />
<br />1935-64
<br />
<br />1935-64
<br />
<br />1.46
<br />
<br />10.7
<br />
<br />69
<br />
<br />19l1-64
<br />
<br />1935- 64
<br />
<br />1.14
<br />
<br />20.9
<br />
<br />53
<br />
<br />1942-64
<br />
<br />1963-64
<br />
<br />,56
<br />
<br />7.5
<br />
<br />104
<br />
<br />1909-64
<br />
<br />1942-64
<br />
<br />1.57
<br />
<br />11. 6
<br />
<br />22
<br />
<br />1952-64
<br />
<br />1952-64
<br />
<br />.24
<br />
<br />161
<br />
<br />1922-64
<br />
<br />1956-64
<br />
<br />7.9
<br />
<br />1.16
<br />
<br />12
<br />
<br />1959-64
<br />
<br />1959-64
<br />
<br />12.6
<br />
<br />TABLE 2(b) STATION CHARACTERISTICS - THE UPPER 8ASIN OF THE COLORADO RIVER
<br />
<br />CSU IO
<br />(U.S,G.S,
<br />No.)
<br />
<br />1762500
<br />(9,0400)
<br />1800900
<br />(9.0355)
<br />1801800
<br />(9,0330)
<br />1801816
<br />(9.0320)
<br />1802730
<br />(9,0265)
<br />1804500
<br />(9,0250)
<br />1805400
<br />(9,0240)
<br />1810000
<br />(9.0210)
<br />1850000
<br />(9.0180)
<br />1866000
<br />(9.0165)
<br />1880000
<br />(9,0155)
<br />1920000
<br />(9,0135)
<br />1930000
<br />(9.0ll5)
<br />1960000
<br />(9,01l0)
<br />
<br />Name
<br />
<br />East Fork Troublesome
<br />Creek near Traub lesome
<br />Strawberry Creek
<br />near Granbv
<br />Meadow Cre~k
<br />near Tabernash
<br />Ranch Creek
<br />near Fraser
<br />5t. Louis Creek
<br />near Fraser
<br />Vasquez Creek
<br />near Winter Park
<br />Frazer River
<br />near Winter Park
<br />Willow Creek below
<br />Willow Creek Res.
<br />Stillwater Creek
<br />above Lake Granby
<br />Arapaho Creek
<br />at Monarch Outlet
<br />Columbine Creek
<br />above Lake Granby
<br />East Inlet near
<br />Grand Lake
<br />North Inlet at
<br />at Grand Lake
<br />Colorado River
<br />near Grand Lake
<br />
<br />Location
<br />Lati tude
<br />Longi t.ude
<br />
<br />40 9 27
<br />106 16 58
<br />40 5 10
<br />105 49 30
<br />40 2 55
<br />105 46 30
<br />39 57 0
<br />105 45 54
<br />3g 54 30
<br />105 52 45
<br />39 55 13
<br />105 47 5
<br />39 54 0
<br />105 46 35
<br />40 8 45
<br />105 56 22
<br />40 II 20
<br />105 53 40
<br />40 6 45
<br />105 44 57
<br />40 II 20
<br />105 49 0
<br />40 14 20
<br />105 48 0
<br />40 15 0
<br />105 49 50
<br />40 13 8
<br />105 51 25
<br />
<br />Elevation
<br />feet
<br />
<br />7750
<br />
<br />8650
<br />
<br />9780
<br />
<br />8670
<br />
<br />8980
<br />
<br />8769
<br />
<br />8900
<br />
<br />8024
<br />
<br />8310
<br />
<br />8310
<br />
<br />8282
<br />
<br />8371
<br />
<br />8380
<br />
<br />8380
<br />
<br />Drainage
<br />Area
<br />mile2
<br />
<br />134.0
<br />
<br />103.0 '
<br />
<br />76.0
<br />
<br />12,6
<br />
<br />7.0
<br />
<br />19,9
<br />
<br />32.8
<br />
<br />27,8
<br />
<br />27,6
<br />
<br />18.8
<br />
<br />47.1
<br />
<br />7.3
<br />
<br />27,1
<br />
<br />46.6
<br />
<br />Recording
<br />Length
<br />
<br />Continuous
<br />Recording
<br />Length
<br />
<br />Mean (inch)
<br />& variance
<br />(inch2)
<br />Annual Spring
<br />
<br />4.95
<br />4,46
<br />6.92
<br />4,57
<br />20,92
<br />23.66
<br />11.30
<br />26.92
<br />12.99
<br />19.95
<br />7,10
<br />24,21
<br />14.84
<br />64.70
<br />4.08
<br />10,84
<br />7.45
<br />9,35
<br />23.79
<br />24,78
<br />12.56
<br />22.39
<br />21. 77
<br />26,62
<br />19.99
<br />30.44
<br />15,17
<br />25.34
<br />
<br />4,04
<br />4.32
<br />5.71
<br />3.90
<br />19,00
<br />65,24
<br />8.98
<br />26,92
<br />9.27
<br />16,18
<br />5,05
<br />12,00
<br />10.99
<br />23,74
<br />2.72
<br />6,39
<br />6.42
<br />3,24
<br />19.94
<br />22.98
<br />10.36
<br />88,21
<br />18.83
<br />29.28
<br />16,89
<br />17,31
<br />12.28
<br />12, II
<br />
<br />Ratio of
<br />spring to
<br />annual
<br />runoff
<br />
<br />Increase
<br />in
<br />runoff
<br />(inch)
<br />
<br />,82
<br />
<br />,83
<br />
<br />.91
<br />
<br />.80
<br />
<br />.71
<br />
<br />.71
<br />
<br />,74
<br />
<br />.67
<br />
<br />.86
<br />
<br />.84
<br />
<br />.83
<br />
<br />.87
<br />
<br />,84
<br />
<br />,81
<br />
<br />Number of
<br />Increase years for
<br />Percentage Evaluation
<br />
<br />.31
<br />
<br />7.7
<br />
<br />173
<br />
<br />1937-64
<br />
<br />1954-64
<br />
<br />,51
<br />
<br />8.9
<br />
<br />57
<br />
<br />1936- 45
<br />
<br />1936-45
<br />
<br />1.39
<br />
<br />7.3
<br />
<br />181
<br />
<br />1936-56
<br />
<br />1936-56
<br />
<br />.65
<br />
<br />16,3
<br />
<br />245
<br />
<br />1934-64
<br />
<br />1934-64
<br />
<br />,66
<br />
<br />7.1
<br />
<br />143
<br />
<br />1934-64
<br />
<br />1934-64
<br />
<br />,75
<br />
<br />14.9
<br />
<br />81
<br />
<br />1907-64
<br />
<br />1934-64
<br />
<br />,26
<br />
<br />2.4
<br />
<br />1349
<br />
<br />19l1-64
<br />
<br />19l1-64
<br />
<br />.55
<br />
<br />20.2
<br />
<br />81
<br />
<br />1953-64
<br />
<br />1953-64
<br />
<br />,85
<br />
<br />13.3
<br />
<br />17
<br />
<br />1950- 56
<br />
<br />1950-56
<br />
<br />1.52
<br />
<br />7.7
<br />
<br />38
<br />
<br />1945-64
<br />
<br />1945-64
<br />
<br />,95
<br />
<br />9.2
<br />
<br />375
<br />
<br />1950-56
<br />
<br />1950-56
<br />
<br />1.57
<br />
<br />8.3
<br />
<br />46
<br />
<br />1948-56
<br />
<br />1948-56
<br />
<br />1.36
<br />
<br />8.1
<br />
<br />36
<br />
<br />1950-56
<br />
<br />1950-56
<br />
<br />.92
<br />
<br />7.5
<br />
<br />55
<br />
<br />1904- 64
<br />
<br />1934-64
<br />
<br />24
<br />
|