#Ryan O: http://www.climateaudit.org/?p=5341#comment-351036

mask.pen=c(1:114, 117:131, 140:156, 166:186, 195:214, 223:242, 250:268, 278:296, 310:327, 345:360, 383:397, 420:434, 461:471, 504:510, 545:549)
mask.west.a=c(115, 116, 132:139, 157:165, 187:194, 215:222, 243:249, 269:277, 297:309, 328:344, 361:382, 398:419, 435:456, 472:495, 511:535, 550:575, 587:615, 628:657, 670:700, 714:743, 758:787, 802:832, 849:878, 897:924, 944:970, 995:1020, 1050:1074, 1107:1131, 1169:1184, 1233:1246, 1298:1310, 1362:1374, 1428:1440, 1497:1500, 1564:1565)
mask.ross=c(1185:1192, 1247:1256, 1311:1319, 1375:1383, 1441:1449, 1501:1516, 1566:1582, 1633:1649, 1700:1717, 1769:1785, 1839:1854, 1910:1925, 1981:1996, 2052:2066, 2123:2136, 2193:2206, 2265:2277, 2337:2348, 2408:2419, 2481:2489)
mask.west=c(mask.west.a, mask.ross)
mask.east=seq(1:5509)
mask.east[c(mask.pen, mask.west)]=NA
mask.east=as.vector(na.omit(mask.east))