Comparing Cold Climates with the Pomologica Atlas

i've been working on some maps using public temp and zone data for canada but also to make sense of comparable european and northern russia and china areas. it on pomologica.ca at the bottom under atlas. it tries to pin research stations and major cities and help show what the climate and temp extremes really are, I think about this when I want to grow a sweet cherry bred in Lenningrad known for northern cold hardiness, or a Russian pear from an area that's quite cold - well is that like here or ten degrees warmer in the winter? these temperature band maps try and answer that, and they go along with different winter injury scales, and the systems used by other countries