Particles are just so cool, and so very useful. Scientists can learn about the past — for example, past climate — using “carbon dating”, a combination of biology and nuclear physics.
In this article in Geophysics Letters, covered in this Colorado University press release (with a somewhat inaccurate title), the abstract contains the statements…
…the extent to which recent Arctic warming has been anomalous with respect to long-term natural climate variability remains uncertain. Here we use 145 radiocarbon dates on rooted tundra plants revealed by receding cold-based ice caps in the Eastern Canadian Arctic to show that 5000 years of regional summertime cooling has been reversed, with average summer temperatures of the last ~100 years now higher than during any century in more than 44,000 years,…
Now how does this work?