Yes, the lack of geostationary satellite coverage over the Indian Ocean and limited use of NOAA AVHRR polar orbiting imagery is apparent in that step-wise increase. (climateaudit.org)
Plus polar crafts fill gaps in coverage, he says: «There's really no imagery for Alaska, for example, if you rely just on geostationary satellites.» (sciencemag.org)
Trevor Paglen, Four Geostationary Satellites Above the Sierra Nevada, 48 x 60 inches, C - Print, 2007. (artfcity.com)