Thematic Maps

Thematic maps are meant to show a certain theme rather than many all put together in one map. In these maps they are showing the seasons for different pollens across the country. The common theme in these are the type of pollen and the location where the seasons are. http://www.google.com/imgres?imgurl=http://library.buffalo.edu/libraries/asl/maps/img/pollen-season-maps_lrg.jpg&imgrefurl=http://library.buffalo.edu/maps/mapresources/mapsinnewsarticles.php&usg=__NVLbM1Y9javuLgP_nFt1Gy6fFUw=&h=559&w=603&sz=170&hl=en&start=0&zoom=1&tbnid=HHHrZp9_hevsgM:&tbnh=125&tbnw=135&ei=YzkiTvr3Fo6btweE6uGlAw&prev=/search%3Fq%3DThematic%2Bmaps%26um%3D1%26hl%3Den%26sa%3DN%26biw%3D1363%26bih%3D740%26tbm%3Disch&um=1&itbs=1&iact=hc&vpx=533&vpy=260&dur=5878&hovh=216&hovw=233&tx=83&ty=121&page=1&ndsp=26&ved=1t:429,r:9,s:0&biw=1363&bih=740