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> A lot of ocean water is already covered by something else with albedo: clouds. Particularly in the poles, clouds tend to form very easily. You are wrong. An

> A lot of ocean water is already covered by something else with albedo: clouds. Particularly in the poles, clouds tend to form very easily. You are wrong. Antarctica is the driest place on Earth. https://www.google.com/search?q=driest+continent+on+earth https://www.google.com/search?q=driest+continent+on+earth "Antarctica is the driest continent; it is almost entirely desert. Very little snow or rain falls on the continent (...)" Dry == not much cloud cover. And if there are ice crystals in atmosphere it mostly shows as haze, it is not effective at reflecting large portion of the sunlight. Clouds form from moisture from evaporating water. This usually requires warm water to be significant. In northern hemisphere this warm water is supplied by Gulf Stream. Also, as a side note, clouds are not nearly as effective at reflecting energy back to space as snow is. First, ice is there all the time, every day. Clouds are rarely continuous for long periods. Second, clouds are scattering light. Of which some goes back to space. Snow is reflecting it. I know on picture they both look white because humans are poor at discerning levels of whiteness. https://en.wikipedia.org/wiki/Cloud_albedo https://en.wikipedia.org/wiki/Cloud_albedo "Cloud albedo on a planet varies from less than 10% to more than 90% and depends on drop sizes, liquid water or ice content, thickness of the cloud, solar zenith angle, etc Clean snow has albedo of 90%, which is the best clouds can get in optimal conditions, but rarely actually get there. And difference between 90% and 80% of albedo is TWICE the amount of energy absorbed. Without it there is not going to be a lot of clouds and rain in northern Canada or Europe. And arctic is already quite dry.

chrisco255 5y ago
Of course, my comment was on cloud cover above water, near the poles, including the water surrounding Antarctica, which has frequent snowfall including as we speak. Take a look at current satellite imagery of the area surrounding Antarctica: https://www.windy.com/-Satellite-satellite?satellite,-63.744,44.517,4 https://www.windy.com/-Satellite-satellite?satellite,-63.744... Cloud cover is more common over ocean water than on land. Also, Antarctica's cloud cover is larger in the winter than in the summer: "The seasonal cycle of cloud cover is found to range from 45%–50% during the short summer to a relatively constant 55%–65% during the winter. " https://journals.ametsoc.org/configurable/content/journals$002fclim$002f20$002f3$002fjcli4005.1.xml?t:ac=journals%24002fclim%24002f20%24002f3%24002fjcli4005.1.xml https://journals.ametsoc.org/configurable/content/journals$0... You can find similar studies on the cloud cover above exposed water in the Arctic. It doesn't matter how variable clouds are, what matters is an average over a long period of time. Clouds have a far more dramatic effect on global temperatures, because they have the ability to reflect absorption of solar energy in the hottest parts of the planet (the tropics), where ice cannot exist. They can and do form over most of the ocean water which covers 2/3 of the planet's surface. Average cloud cover over ocean water is 90%! Some clouds scatter light. Some are extremely effective at reflecting light into space. Depends on zenith angle of the light (based on latitude), the altitude of the cloud, water content and shape and thickness overall. https://www.researchgate.net/publication/334183298_High_cloud_coverage_over_melted_areas_dominates_the_impact_of_clouds_on_the_albedo_feedback_in_the_Arctic https://www.researchgate.net/publication/334183298_High_clou...

chrisco255 5y ago

Of course, my comment was on cloud cover above water, near the poles, including the water surrounding Antarctica, which has frequent snowfall including as we speak. Take a look at current satellite imagery of the area surrounding Antarctica: https://www.windy.com/-Satellite-satellite?satellite,-63.744,44.517,4 https://www.windy.com/-Satellite-satellite?satellite,-63.744... Cloud cover is more common over ocean water than on land. Also, Antarctica's cloud cover is larger in the winter than in the summer: "The seasonal cycle of cloud cover is found to range from 45%–50% during the short summer to a relatively constant 55%–65% during the winter. " https://journals.ametsoc.org/configurable/content/journals$002fclim$002f20$002f3$002fjcli4005.1.xml?t:ac=journals%24002fclim%24002f20%24002f3%24002fjcli4005.1.xml https://journals.ametsoc.org/configurable/content/journals$0... You can find similar studies on the cloud cover above exposed water in the Arctic. It doesn't matter how variable clouds are, what matters is an average over a long period of time. Clouds have a far more dramatic effect on global temperatures, because they have the ability to reflect absorption of solar energy in the hottest parts of the planet (the tropics), where ice cannot exist. They can and do form over most of the ocean water which covers 2/3 of the planet's surface. Average cloud cover over ocean water is 90%! Some clouds scatter light. Some are extremely effective at reflecting light into space. Depends on zenith angle of the light (based on latitude), the altitude of the cloud, water content and shape and thickness overall. https://www.researchgate.net/publication/334183298_High_cloud_coverage_over_melted_areas_dominates_the_impact_of_clouds_on_the_albedo_feedback_in_the_Arctic https://www.researchgate.net/publication/334183298_High_clou...