Pixel Values

Raw rasters are in provided in 8-bit unsigned pixel depth (with values ranging from 0-255) with their original color table. Raw pixel values can be mapped to cyano index (CI) (for cyano products), chlorophyll-a concentration (for chlorophyll products), or no-data values as shown in the table below.

Additionally, the table provides estimated conversions from CI to estimated Microcystis sp. equivalent cell concentration, borrowing from NOAA's efforts to monitor cyanobacteria blooms in Lake Erie. These conversions have not be field verified for water bodies in California and are provided only for reference.

1Only applies to CI products.
2Only applies to chlorophyll products.
3Threshold for this notification corresponds with the World Health Organization Alert Level 1 threshold.

Color Pixel
Value		 Cyano
Index1 (CI)		 Microcystis sp.1
(cells/mL)		 Chlorophyll-a2
(μg/L)		 Comments
255 No Data
254 No Data (Invalid)
253 No Data (Cloud)
252 No Data (Land)
251 No Data (Adjacency)
250 >6.327e-02 >6,327,038 ≥134.60 Maximum Detectable Level
249 6.155e-02 6,154,541 129.09
248 5.987e-02 5,986,747 123.87
247 5.824e-02 5,823,527 118.93
246 5.665e-02 5,664,757 114.27
245 5.510e-02 5,510,316 109.90
244 5.360e-02 5,360,085 105.81
243 5.214e-02 5,213,950 102.01
242 5.072e-02 5,071,799 98.49
241 4.934e-02 4,933,524 95.25
240 4.799e-02 4,799,019 92.30
239 4.668e-02 4,668,181 89.29
238 4.541e-02 4,540,910 86.45
237 4.417e-02 4,417,108 83.78
236 4.297e-02 4,296,682 81.29
235 4.180e-02 4,179,540 78.96
234 4.066e-02 4,065,591 76.80
233 3.955e-02 3,954,748 74.63
232 3.847e-02 3,846,928 72.57
231 3.742e-02 3,742,047 70.62
230 3.640e-02 3,640,026 68.80
229 3.541e-02 3,540,786 66.98
228 3.444e-02 3,444,251 65.23
227 3.350e-02 3,350,349 63.55
226 3.259e-02 3,259,007 61.94
225 3.170e-02 3,170,154 60.41
224 3.084e-02 3,083,725 58.94
223 3.000e-02 2,999,652 57.55
222 2.918e-02 2,917,871 56.23
221 2.838e-02 2,838,319 54.98
220 2.761e-02 2,760,936 53.80
219 2.686e-02 2,685,664 52.56
218 2.612e-02 2,612,443 51.36
217 2.541e-02 2,541,218 50.22
216 2.472e-02 2,471,936 49.12
215 2.405e-02 2,404,542 48.06
214 2.339e-02 2,338,986 47.06
213 2.275e-02 2,275,217 46.10
212 2.213e-02 2,213,186 45.18
211 2.153e-02 2,152,847 44.32
210 2.094e-02 2,094,153 43.50
209 2.037e-02 2,037,059 42.62
208 1.982e-02 1,981,522 41.76
207 1.927e-02 1,927,498 40.94
206 1.875e-02 1,874,948 40.14
205 1.824e-02 1,823,830 39.36
204 1.774e-02 1,774,106 38.62
203 1.726e-02 1,725,738 37.90
202 1.679e-02 1,678,688 37.20
201 1.633e-02 1,632,921 36.54
200 1.588e-02 1,588,402 35.90
199 1.545e-02 1,545,096 35.24
198 1.503e-02 1,502,972 34.60
197 1.462e-02 1,461,995 33.97
196 1.422e-02 1,422,136 33.36
195 1.383e-02 1,383,364 32.77
194 1.346e-02 1,345,648 32.20
193 1.309e-02 1,308,961 31.65
192 1.273e-02 1,273,274 31.12
191 1.239e-02 1,238,560 30.60
190 1.205e-02 1,204,793 30.10
189 1.172e-02 1,171,946 29.59
188 1.140e-02 1,139,994 29.08
187 1.109e-02 1,108,914 28.59
186 1.079e-02 1,078,681 28.12
185 1.049e-02 1,049,273 27.65
184 1.021e-02 1,020,666 27.20 'Very High' Estimated Abundance Threshold1
183 9.928e-03 992,839 26.75
182 9.658e-03 965,770 26.32
181 9.394e-03 939,440 25.91
180 9.138e-03 913,828 25.50
179 8.889e-03 888,914 25.09
178 8.647e-03 864,679 24.69
177 8.411e-03 841,104 24.30
176 8.182e-03 818,173 23.91
175 7.959e-03 795,867 23.54
174 7.742e-03 774,169 23.17
173 7.531e-03 753,062 22.82
172 7.325e-03 732,531 22.47
171 7.126e-03 712,560 22.13
170 6.931e-03 693,133 21.80
169 6.742e-03 674,235 21.46
168 6.559e-03 655,853 21.13
167 6.380e-03 637,972 20.81
166 6.206e-03 620,579 20.49
165 6.037e-03 603,660 20.18
164 5.872e-03 587,202 19.87
163 5.712e-03 571,193 19.57
162 5.556e-03 555,620 19.27
161 5.405e-03 540,472 18.98
160 5.257e-03 525,737 18.70
159 5.114e-03 511,403 18.42
158 4.975e-03 497,461 18.15
157 4.839e-03 483,898 17.89
156 4.707e-03 470,705 17.63
155 4.579e-03 457,872 17.37
154 4.454e-03 445,389 17.13
153 4.332e-03 433,246 16.89
152 4.214e-03 421,434 16.65
151 4.099e-03 409,944 16.42
150 3.988e-03 398,768 16.20
149 3.879e-03 387,896 15.97
148 3.773e-03 377,321 15.74
147 3.670e-03 367,034 15.51
146 3.570e-03 357,027 15.28
145 3.473e-03 347,293 15.06
144 3.378e-03 337,825 14.84
143 3.286e-03 328,614 14.63
142 3.197e-03 319,655 14.42
141 3.109e-03 310,940 14.21
140 3.025e-03 302,463 14.00
139 2.942e-03 294,217 13.80
138 2.862e-03 286,195 13.60
137 2.784e-03 278,393 13.40
136 2.708e-03 270,803 13.20
135 2.634e-03 263,420 13.01
134 2.562e-03 256,238 12.82
133 2.493e-03 249,252 12.64
132 2.425e-03 242,456 12.46
131 2.358e-03 235,846 12.28
130 2.294e-03 229,416 12.10 36CI FHAB Notification Threshold3
129 2.232e-03 223,162 11.92
128 2.171e-03 217,077 11.74
127 2.112e-03 211,159 11.57
126 2.054e-03 205,402 11.40
125 1.998e-03 199,802 11.23
124 1.944e-03 194,355 11.06
123 1.891e-03 189,056 10.89
122 1.839e-03 183,902 10.72
121 1.789e-03 178,888 10.56
120 1.740e-03 174,011 10.40
119 1.693e-03 169,267 10.25
118 1.647e-03 164,652 10.10
117 1.602e-03 160,163 9.95
116 1.558e-03 155,796 9.80
115 1.515e-03 151,549 9.66
114 1.474e-03 147,417 9.52
113 1.434e-03 143,398 9.39
112 1.395e-03 139,488 9.26
111 1.357e-03 135,685 9.13
110 1.320e-03 131,986 9.00
109 1.284e-03 128,388 8.87
108 1.249e-03 124,887 8.73
107 1.215e-03 121,482 8.60
106 1.182e-03 118,170 8.47
105 1.149e-03 114,949 8.34
104 1.118e-03 111,815 8.21
103 1.088e-03 108,766 8.08
102 1.058e-03 105,801 7.95
101 1.029e-03 102,916 7.83
100 1.001e-03 100,111 7.70 'High' Estimated Abundance Threshold1
99 9.738e-04 97,381 7.58
98 9.473e-04 94,726 7.45
97 9.214e-04 92,144 7.33
96 8.963e-04 89,632 7.21
95 8.719e-04 87,188 7.09
94 8.481e-04 84,811 6.97
93 8.250e-04 82,499 6.85
92 8.025e-04 80,249 6.73
91 7.806e-04 78,062 6.62
90 7.593e-04 75,933 6.50
89 7.386e-04 73,863 6.39
88 7.185e-04 71,849 6.28
87 6.989e-04 69,890 6.18
86 6.798e-04 67,985 6.08
85 6.613e-04 66,132 5.98
84 6.433e-04 64,328 5.88
83 6.257e-04 62,575 5.78
82 6.087e-04 60,869 5.68
81 5.921e-04 59,209 5.59
80 5.759e-04 57,595 5.50
79 5.602e-04 56,025 5.41
78 5.450e-04 54,497 5.31
77 5.301e-04 53,012 5.22
76 5.157e-04 51,566 5.13
75 5.016e-04 50,160 5.04
74 4.879e-04 48,793 4.95
73 4.746e-04 47,462 4.86
72 4.617e-04 46,168 4.77
71 4.491e-04 44,910 4.69
70 4.369e-04 43,685 4.60
69 4.249e-04 42,494 4.51
68 4.134e-04 41,336 4.43
67 4.021e-04 40,209 4.34
66 3.911e-04 39,113 4.26
65 3.805e-04 38,046 4.17
64 3.701e-04 37,009 4.09
63 3.600e-04 36,000 4.01
62 3.502e-04 35,018 3.92
61 3.406e-04 34,064 3.84
60 3.314e-04 33,135 3.76
59 3.223e-04 32,232 3.68
58 3.135e-04 31,353 3.60
57 3.050e-04 30,498 3.52
56 2.967e-04 29,667 3.44
55 2.886e-04 28,858 3.37
54 2.807e-04 28,071 3.29
53 2.731e-04 27,306 3.21
52 2.656e-04 26,561 3.14
51 2.584e-04 25,837 3.06
50 2.513e-04 25,133 2.99
49 2.445e-04 24,448 2.92
48 2.378e-04 23,781 2.84
47 2.313e-04 23,133 2.77
46 2.250e-04 22,502 2.70
45 2.189e-04 21,888 2.63
44 2.129e-04 21,292 2.56
43 2.071e-04 20,711 2.49
42 2.015e-04 20,147 2.42 NOAA Minimum Risk Threshold1 / 'Moderate' Estimated Abundance Threshold1
41 1.960e-04 19,597 2.36
40 1.906e-04 19,063 2.29
39 1.854e-04 18,543 2.22
38 1.804e-04 18,038 2.16
37 1.755e-04 17,546 2.09
36 1.707e-04 17,068 2.03
35 1.660e-04 16,602 1.96
34 1.615e-04 16,150 1.90
33 1.571e-04 15,709 1.84
32 1.528e-04 15,281 1.77
31 1.486e-04 14,864 1.71
30 1.446e-04 14,459 1.65
29 1.407e-04 14,065 1.59
28 1.368e-04 13,682 1.53
27 1.331e-04 13,308 1.47
26 1.295e-04 12,946 1.41
25 1.259e-04 12,593 1.35
24 1.225e-04 12,249 1.29
23 1.192e-04 11,915 1.23
22 1.159e-04 11,591 1.17
21 1.127e-04 11,275 1.12
20 1.097e-04 10,967 1.06
19 1.067e-04 10,668 1.00
18 1.038e-04 10,377 0.95
17 1.009e-04 10,094 0.89
16 9.819e-05 9,819 0.84
15 9.551e-05 9,552 0.78
14 9.291e-05 9,291 0.73
13 9.038e-05 9,038 0.67
12 8.791e-05 8,791 0.62
11 8.552e-05 8,552 0.56
10 8.319e-05 8,319 0.51
9 8.092e-05 8,092 0.46
8 7.871e-05 7,871 0.40
7 7.657e-05 7,657 0.35
6 7.448e-05 7,448 0.30
5 7.245e-05 7,245 0.25
4 7.047e-05 7,047 0.20
3 6.855e-05 6,855 0.15
2 6.668e-05 6,668 0.10
1 6.486e-05 6,486 <0.05 Background Level2
0 ≤6.310e-05 ≤6,310 Background Level1 / Non-Detect2

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