Eli5 water displacement question, I think.

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Ok, so my question is rather dumb and I apologise in advance.

If I have 500ml of warm water, and I place exactly 500ml of ice into said water, when it melts will it make it up to 1L?, and if so why is global warming such an issue because isn’t there more water on earth than there is ice, so wouldn’t it just melt away. (I’m not taking away from the fact global warming I not an issue) I was just making something that needed to cool quick so I put ice in it and it made me curious!!

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27 Answers

Anonymous 0 Comments

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Anonymous 0 Comments

It’s weird to measure a solid in terms of volume, but ice is about 90% as dense as water. If you placed 500 mL of ice into water, after it melts it will only take up 450 mL of volume and you’ll be left with 950 mL of water.

The problem with melting ice is for example the ice sheet covering Greenland, which will add new water to the oceans as it melts

Anonymous 0 Comments

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Anonymous 0 Comments

It’s weird to measure a solid in terms of volume, but ice is about 90% as dense as water. If you placed 500 mL of ice into water, after it melts it will only take up 450 mL of volume and you’ll be left with 950 mL of water.

The problem with melting ice is for example the ice sheet covering Greenland, which will add new water to the oceans as it melts

Anonymous 0 Comments

Ice at or near melting temperature is less dense than water at or near melting temperature, so if you put 500 mL of ice into 500 mL of water and it all melts, you get less than a liter of water at the end of it.

As /u/aetherialClockwork mentioned, the sea level rise associated with global warming’s melting of ice is due to ice that is currently on land (or other ice) and not already in the water. In your example, you start with 500 mL of water. You add 500 mL of ice to the water and you get almost a liter of water. The important part is not that you get slightly less than a liter, but the fact that your ice went from being outside the water (like a glacier) to being immersed in the water (like a glacier calving into the ocean) and melting. The total volume of liquid nearly doubled.

Anonymous 0 Comments

>If I have 500ml of warm water, and I place exactly 500ml of ice into said water, when it melts will it make it up to 1L?,

No, it’ll be around 950 mL.

Ice is less dense than water so while the 500 mL of warm water weighs about 500 grams, the 500 mL of ice is closer to 460 grams

The concern with global warming isn’t that sea ice melts, it’s that glaciers that are currently over land melt

The ice sheets over northern Russia, Canada, Alaska, and Antarctica don’t fully melt and because they’re supported by land they’re not displacing ocean water. But when they melt their water runs down and into the ocean thus raising the sea level

Anonymous 0 Comments

Man, all you guys are so fucking smart. This is why I love this subreddit, because I can ask the dumbest questions and not get my ass kicked. Haha. Thank you all.

Anonymous 0 Comments

The ice isn’t all sitting in the water, it’s frozen on land and on mountaintops. If it all melts, it returns to the ocean.

Anonymous 0 Comments

Man, all you guys are so fucking smart. This is why I love this subreddit, because I can ask the dumbest questions and not get my ass kicked. Haha. Thank you all.