These include that the land, borehole and marine records substantially agree; and the fact that there is little difference between the long - term (1880 to 1998) rural (0.70 °C / century) and full set of station temperature trends (actually less at 0.65 °C / century). (realclimate.org)
Tremblay, L.B., G.A. Schmidt, S. Pfirman, R. Newton, and P. DeRepentigny, 2015: Is ice - rafted sediment in a North Pole marine record evidence for perennial sea - ice cover? (pubs.giss.nasa.gov)
These samples augment other marine records such as coral and seashells, which provide detailed records over a short time period, and deep - ocean sediments, which preserve thousands of years of history but are harder to date precisely. (sciencedaily.com)