High Level (Cirriform) Frequency of Occurrence (%) September (1954 - 1997) , Ship Observations Only Global Average: 32.3 Zonal Averages 15 zones Lat.N Average 85 54.0 75 39.4 65 39.5 55 37.2 45 36.4 35 33.0 25 33.2 15 43.2 5 44.9 -5 31.0 -15 22.5 -25 22.9 -35 26.9 -45 30.5 -55 25.2 Grid Box Averages 343 filled boxes Box # Lat.N Lon.E Average 1 85 60 46.9 2 85 180 56.1 3 85 300 61.0 4 75 20 35.4 5 75 60 31.8 6 75 100 30.0 7 75 140 35.1 8 75 180 43.0 9 75 220 50.9 10 75 260 49.5 11 75 300 39.4 12 75 340 36.5 13 65 10 39.5 14 65 30 35.6 15 65 50 31.8 16 65 70 26.4 20 65 150 29.8 21 65 170 28.2 22 65 190 36.7 23 65 210 54.8 25 65 250 51.4 26 65 270 47.3 27 65 290 46.6 28 65 310 40.9 29 65 330 39.4 30 65 350 38.1 31 55 10 41.3 32 55 30 35.5 37 55 130 41.8 38 55 150 30.9 39 55 170 32.3 40 55 190 40.2 41 55 210 37.5 42 55 230 40.1 44 55 270 52.6 45 55 290 41.2 46 55 310 34.3 47 55 330 34.2 48 55 350 42.9 49 45 5 37.9 50 45 15 28.7 51 45 25 17.2 52 45 35 14.1 53 45 45 16.3 54 45 55 15.9 62 45 135 31.8 63 45 145 33.2 64 45 155 37.5 65 45 165 39.5 66 45 175 41.7 67 45 185 42.4 68 45 195 43.5 69 45 205 41.4 70 45 215 37.8 71 45 225 32.5 72 45 235 31.0 77 45 285 38.0 78 45 295 35.9 79 45 305 35.9 80 45 315 37.7 81 45 325 34.9 82 45 335 33.1 83 45 345 34.1 84 45 355 36.6 85 35 5 31.0 86 35 15 21.1 87 35 25 9.7 88 35 35 6.3 90 35 55 19.6 96 35 115 28.1 97 35 125 35.1 98 35 135 45.2 99 35 145 45.0 100 35 155 39.7 101 35 165 39.5 102 35 175 39.9 103 35 185 43.5 104 35 195 40.0 105 35 205 33.8 106 35 215 28.6 107 35 225 21.5 108 35 235 18.8 109 35 245 16.3 112 35 275 46.3 113 35 285 41.8 114 35 295 36.8 115 35 305 36.0 116 35 315 36.0 117 35 325 31.3 118 35 335 28.0 119 35 345 23.1 120 35 355 29.8 124 25 35 11.9 125 25 45 5.3 126 25 55 7.1 127 25 65 18.4 128 25 75 36.4 129 25 85 56.0 130 25 95 69.3 131 25 105 53.8 132 25 115 41.6 133 25 125 39.7 134 25 135 47.5 135 25 145 43.4 136 25 155 36.6 137 25 165 35.9 138 25 175 36.6 139 25 185 37.3 140 25 195 30.0 141 25 205 25.2 142 25 215 22.4 143 25 225 22.6 144 25 235 23.8 145 25 245 26.5 146 25 255 45.0 147 25 265 47.9 148 25 275 53.1 149 25 285 47.4 150 25 295 41.1 151 25 305 35.4 152 25 315 30.6 153 25 325 23.1 154 25 335 19.3 155 25 345 18.9 160 15 35 22.5 161 15 45 20.8 162 15 55 17.5 163 15 65 30.0 164 15 75 49.0 165 15 85 53.1 166 15 95 60.6 167 15 105 57.8 168 15 115 52.6 169 15 125 52.3 170 15 135 57.1 171 15 145 58.0 172 15 155 50.2 173 15 165 43.4 174 15 175 44.0 175 15 185 47.4 176 15 195 40.1 177 15 205 34.9 178 15 215 34.8 179 15 225 32.7 180 15 235 33.0 181 15 245 43.0 182 15 255 56.3 183 15 265 63.8 184 15 275 62.6 185 15 285 51.0 186 15 295 43.0 187 15 305 37.5 188 15 315 34.0 189 15 325 29.7 190 15 335 29.1 191 15 345 36.2 193 5 5 48.0 197 5 45 22.0 198 5 55 26.8 199 5 65 40.0 200 5 75 51.9 201 5 85 61.9 202 5 95 70.5 203 5 105 59.8 204 5 115 59.5 205 5 125 60.4 206 5 135 60.5 207 5 145 58.0 208 5 155 56.7 209 5 165 53.3 210 5 175 50.3 211 5 185 47.7 212 5 195 40.9 213 5 205 36.3 214 5 215 38.1 215 5 225 31.1 216 5 235 32.9 217 5 245 32.3 218 5 255 42.9 219 5 265 51.3 220 5 275 62.3 221 5 285 60.8 223 5 305 37.8 224 5 315 26.9 225 5 325 22.9 226 5 335 30.9 227 5 345 37.7 228 5 355 28.6 229 -5 5 21.9 230 -5 15 21.9 232 -5 35 16.6 233 -5 45 18.0 234 -5 55 28.5 235 -5 65 50.5 236 -5 75 51.9 237 -5 85 61.6 238 -5 95 61.6 239 -5 105 51.2 240 -5 115 39.5 241 -5 125 35.9 242 -5 135 37.4 243 -5 145 55.1 244 -5 155 51.4 245 -5 165 47.9 246 -5 175 45.0 247 -5 185 44.5 248 -5 195 28.3 249 -5 205 22.5 250 -5 215 18.8 251 -5 225 9.0 252 -5 235 8.9 253 -5 245 12.4 254 -5 255 17.3 255 -5 265 21.2 256 -5 275 32.7 260 -5 315 18.2 261 -5 325 14.3 262 -5 335 11.9 263 -5 345 12.9 264 -5 355 13.2 265 -15 5 13.8 266 -15 15 16.0 268 -15 35 8.4 269 -15 45 10.0 270 -15 55 15.6 271 -15 65 18.9 272 -15 75 31.7 273 -15 85 34.7 274 -15 95 36.0 275 -15 105 23.3 276 -15 115 14.3 277 -15 125 17.2 278 -15 135 31.6 279 -15 145 23.4 280 -15 155 25.0 281 -15 165 31.0 282 -15 175 36.1 283 -15 185 33.4 284 -15 195 33.1 285 -15 205 21.9 286 -15 215 18.6 287 -15 225 13.8 288 -15 235 15.7 289 -15 245 18.0 290 -15 255 17.0 291 -15 265 20.3 292 -15 275 18.9 293 -15 285 23.3 297 -15 325 23.8 298 -15 335 18.2 299 -15 345 20.0 300 -15 355 19.5 301 -25 5 20.3 302 -25 15 18.4 304 -25 35 14.3 305 -25 45 12.9 306 -25 55 13.3 307 -25 65 16.2 308 -25 75 18.8 309 -25 85 13.5 310 -25 95 16.9 311 -25 105 15.5 312 -25 115 10.3 315 -25 145 10.5 316 -25 155 13.5 317 -25 165 18.2 318 -25 175 22.4 319 -25 185 27.3 320 -25 195 27.3 321 -25 205 33.3 322 -25 215 35.1 323 -25 225 34.3 324 -25 235 27.8 325 -25 245 25.6 326 -25 255 35.9 327 -25 265 26.3 328 -25 275 17.2 329 -25 285 16.1 332 -25 315 34.2 333 -25 325 27.6 334 -25 335 27.1 335 -25 345 27.9 336 -25 355 26.4 337 -35 5 31.9 338 -35 15 25.9 339 -35 25 30.2 340 -35 35 22.5 341 -35 45 23.4 342 -35 55 21.7 343 -35 65 22.1 344 -35 75 21.9 345 -35 85 22.6 346 -35 95 22.4 347 -35 105 19.6 348 -35 115 20.5 349 -35 125 24.9 350 -35 135 27.7 351 -35 145 32.4 352 -35 155 26.3 353 -35 165 25.6 354 -35 175 27.8 355 -35 185 28.1 356 -35 195 26.9 357 -35 205 28.2 358 -35 215 31.7 359 -35 225 31.2 360 -35 235 28.3 361 -35 245 34.1 363 -35 265 37.1 364 -35 275 23.3 365 -35 285 23.6 367 -35 305 34.7 368 -35 315 27.6 369 -35 325 28.9 370 -35 335 22.2 371 -35 345 30.2 372 -35 355 35.2 376 -45 35 30.0 379 -45 65 21.0 380 -45 75 17.7 384 -45 115 36.4 386 -45 135 31.3 387 -45 145 32.3 388 -45 155 28.2 389 -45 165 33.1 390 -45 175 33.7 391 -45 185 37.6 392 -45 195 31.2 393 -45 205 39.8 394 -45 215 24.7 400 -45 275 23.4 401 -45 285 25.9 402 -45 295 41.0 403 -45 305 32.3 404 -45 315 35.3 405 -45 325 27.6 411 -55 50 18.0 412 -55 70 13.2 417 -55 170 31.6 422 -55 270 25.1 423 -55 290 38.3 424 -55 310 32.6 425 -55 330 20.1