div class=ts-pagebutton class=gotoPage data-page=1Page 1button div class=ts-imageimg data-url=thickness-of-ice-on-perennially-frozen-lakeshtmlpage=1 data-page=1 class=ts-thumb lazyload alt=Page 1: Thickness of ice on perennially frozen lakes loading=lazy src=data:imagegifbase64iVBORw0KGgoAAAANSUhEUgAAAAIAAAACCAQAAADYv8WvAAAAD0lEQVR42mP8X8AwAgiABKBAv+vAXklAAAAAElFTkSuQmCC data-src=https:reader035vdocumentsnetreader035viewer2022080321575068701a28ab0f07b02a82html5thumbnails1jpg width=140 height=200 divp© Nature Publishing Group1985pdivdiv class=ts-pagebutton class=gotoPage data-page=2Page 2button div class=ts-imageimg data-url=thickness-of-ice-on-perennially-frozen-lakeshtmlpage=2 data-page=2 class=ts-thumb lazyload alt=Page 2: Thickness of ice on perennially frozen lakes loading=lazy src=data:imagegifbase64iVBORw0KGgoAAAANSUhEUgAAAAIAAAACCAQAAADYv8WvAAAAD0lEQVR42mP8X8AwAgiABKBAv+vAXklAAAAAElFTkSuQmCC data-src=https:reader035vdocumentsnetreader035viewer2022080321575068701a28ab0f07b02a82html5thumbnails2jpg width=140 height=200 divp© Nature Publishing Group1985pdiv