Exploring the digital world!
Humans have roughly 150 years of data from weather stations that have obviously continued improving over that time.
This is a Kaggle dataset for earth surface temperature data. One file has data from 1743 GlobalLandTemperaturesByCity.csv (508.15 MB)
There is some data available from the government:
Datahub attempt to tell us the most important climate datasets: https://datahub.io/collections/climate-change
This is a great visual map of the arctic, http://webmap.arcticconnect.ca/polarmap.js/examples/PolarMap/geosearch/index.html#ac_3573/4/90.00/0.00
Interesting resource that appears to be driven as an open source project on github: https://opensustain.tech/#ice-and-poles