Stanford Science Penpals
Answers to submitted questions will be answered and updated hopefully on a weekly basis. Mickey will try her hardest to answer in a timely manner. Some responses may answer multiple questions that we grouped together. Check out what other people have asked first! Your burning question might have already been answered! ---Science Penpals
Answered Questions
1. When working near glaciers, can you hear the ice crack underneath? (Rhyann - New Mexico)
Glaciers make all kinds of noises! Sometimes there are rivers beneath them so you can hear water flowing. I was once camped near an ice fall in Alaska (see the picture) and I could sometimes hear faint groaning and rumbling noises from the ice deformation. Ice falls are glaciers that are in really steep places. Towards the right side of this image, the ice goes off a cliff, so the ice doesn’t flow slowly like glaciers on flat surfaces. Instead, the ice breaks.
2. How do lakes form under so many ice layers? (LeaRay - New Mexico, Elias - New Mexico)
Ice layers form over hundreds of thousands of years. When snow falls, it will eventually be squeezed into ice. These layers build up over time. In Antarctica, lakes can usually only form under really thick ice because it takes a lot of pressure to force cold ice to melt. Water is an interesting material because it becomes less dense when it freezes (this is why ice cubes float). If you’ve ever accidentally put a bottle of water in the freezer, you’ll know that the ice expands when it freezes and might break your bottle. But if you squeezed the ice hard enough, it would turn into water. This is what’s happening at the bottom of the ice sheet. All the weight from miles of ice pushing down on the ice at the bottom makes it turn to water, even though the temperatures are below freezing. This is what makes subglacial lakes so unusual and exciting! Some glaciologists are searching for life in these lakes. Imagine the kind of creature that could live with no sunlight in below freezing temperatures under several miles of ice!