ナショナルジオグラフィックのインスタグラム(natgeo) - 1月17日 04時18分

Mt. Balfour, background, Yoho NP, Canada. Photo by @peteressick on assignment for @ナショナルジオグラフィック. The Canadian Rockies started forming 100 million years ago when the collision of two crustal plates uplifted and buckled the rock like wrinkles in a rug. The mostly marine sedimentary layers had been collecting for 1.7 billion years, a long time even to a geologist, and eventually became 12 miles thick. In the last 2.6 million years, the Rockies have experienced many glacial advances and retreats. During the cold periods, the ice was over half a mile thick and carved U-shaped valleys between the mountain peaks. Ice ages are caused by fluctuations in the Earth's orbit around the sun and also by the tilt and wobble of the Earth itself. These were relatively predictable until the beginning of the industrial revolution. The 37 percent increase in atmospheric CO2 since then has created greenhouse gases that are melting the remaining glaciers and changing the geological history of this dynamic landscape.

[BIHAKUEN]UVシールド(UVShield)

>> 飲む日焼け止め！「UVシールド」を購入する