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Would it theoreticaly possible to find frozen animals 120.000 years old with still intact DNA?
[0] https://www.theguardian.com/world/2012/feb/21/russian-scient...
This is a very important project. There is a joke in here about "why not wait 2 years for the ice to melt off if you wanted to look at the mud underneath?" But as the article states, "'This will change climate models because it redefines our basic understanding of how ice moves,' explains Dorthe Dahl-Jensen." Much, if not the majority, of climate science is the creation of models (differential equations mostly) that…
All clouds are white, so they all reflect sunlight back into space (during the day), cooling the Earth.
All clouds are (almost) black in the infra-red, meaning the amount of energy they emit in the infra-red is determined by their temperature. Colder clouds emit less energy.
Almost all clouds are colder than the surface beneath them, which means they emit less infra-red energy to space than a clear day would. This reduces the amount of energy the Earth emits to space, so warming the climate.
High clouds are colder than low clouds, so have a stronger warming effect.
In summary:
Low clouds - Reflect sunlight (cooling), don't trap much infra-red (little warming)- Net: Cooling effect
High clouds - Reflect sunlight (cooling), trap lots of infra-red (stronger warming) - Net: Warming effect
Earlier quoted context omitted.
Yeah, DNA in ice has a half-life of a million years. Seems very much possible.
Where are you getting that figure? Everything I had ever read on the subject puts the half-life at more like 500 (five-hundred) years. While doing a quick double-check for this comment, it seems there was one sample with the unexpectedly long observed half-life of 15,000 years, still a couple orders of magnitude less than a million years. https://en.wikipedia.org/wiki/Ancient_DNA#Non-human_aDNA
The DNA we get back from old situations typically was preserved, by dryness/freezing, and it's still quite fragmentary. The actual "half life" of DNA is not that interesting- its the details of the DNA remnants that matter.
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Ice cores are a few inches across. The photo at the top of the article is not of the drill hole but of the hole they had to dig in the snow to get to the ice they actually drilled. See the photo of the final ice core [1] to see how miniscule the actual drill hole is. [1] https://science.ku.dk/english/press/news/2023/pay-dirt-for-i...
The article definitely makes it sound like they had “boots on the ground”. There’s a picture of muddy boots and the caption says they are covered in ancient mud.
I love humans. They somehow decided to start drilling, and not give up & get funding for 7 years. We are a crazy but exciting bunch of organisms.
I read this as "crazy but extinct bunch of organisms"
Earlier quoted context omitted.
Ice cores are a few inches across. The photo at the top of the article is not of the drill hole but of the hole they had to dig in the snow to get to the ice they actually drilled. See the photo of the final ice core [1] to see how miniscule the actual drill hole is. [1] https://science.ku.dk/english/press/news/2023/pay-dirt-for-i...
The article definitely makes it sound like they had “boots on the ground”. There’s a picture of muddy boots and the caption says they are covered in ancient mud.
The ancient mud's from hauling up the ice cores, not from standing 3 kilometers deep in a giant hole.
[1] https://icedrill.org/equipment/deep-ice-sheet-coring-drill
That's a rate of about 4.3 centimeters per hour. Can anybody elaborate as to why this process takes so long?
Earlier quoted context omitted.
Yeah, DNA in ice has a half-life of a million years. Seems very much possible.
Where are you getting that figure? Everything I had ever read on the subject puts the half-life at more like 500 (five-hundred) years. While doing a quick double-check for this comment, it seems there was one sample with the unexpectedly long observed half-life of 15,000 years, still a couple orders of magnitude less than a million years. https://en.wikipedia.org/wiki/Ancient_DNA#Non-human_aDNA
This recent news article suggests nematodes actually surviving after 46K years in permafrost. https://www.scientificamerican.com/article/46-000-year-old-w...
Interesting: "Towards the base, the ice is more than 120,000 years old and dates back to the last interglacial period, a time when the atmospheric temperature above Greenland was 5°C warmer than today."
I'm not a scientist so I'm curious why this is interesting.
I'm completely an armchair ponderer.