The White Nights is a nearly three month-long midsummer celebration that heralds the almost 24-hours of sunlight that blesses this northern latitude.

BBC: Living in: St Petersburg

When people began relying heavily on a diet of bread at such a northern latitude, they probably became chronically deficient in vitamin D, for bread is generally low in vitamin D.

WSJ: Matt Ridley on Human Culture's Effect on Genes | Mind & Matter

It provides an outstanding example of the interaction of marine and terrestrial ecosystems as well as extraordinary ecosystem productivity, largely influenced by the formation of seasonal sea ice at the lowest latitude in the northern hemisphere.

UNESCO: Culture

For a number of reasons, computer models with added atmospheric carbon dioxide preferentially warm the mid-and high-latitude land areas of the northern hemisphere that are ice-free, which also enhances summer melting of the relatively shallow ice in the Arctic Ocean.

FORBES: Is Global Warming A Bipolar Disorder?

"The most troubling finding is the marked increase in the tropical waters of the Northern Hemisphere centered around the globe at a latitude of roughly 5 degrees north, " said Strong.

CNN: Warmer tropical waters portend climate change