[1] His research centered on the Quaternary geology of the Baltic Sea region,[2] nevertheless he did also some contributions on the Silurian stratigraphy of Västergötland and Gotland.

[2] A Gotlänning ("Gotlander") by birth Munthe's dialect is reported to have been Gotländska and he was particularly fond of working with issues regarding the island.

He was the editor of SGU's Gotland maps and lectured about its Quaternary geology at the Visby local history society in 1911.

[4] Later he endorsed the idea of an outlet for this lake at the near Degerfors (Svea River) proposed by Lennart von Post in the 1920s.

[3] In 1927 and 1928 he was involved in a controversyabout Svea River through opinion pieces in newspapers with Astrid Cleve,[5] a strident outcast of Sweden's geological community.