Your climate is an aggregate assessment of years of weather data and your hardiness zone is all of that info, including highs, lows, precip., etc., boiled down into one number. I live in zone 4, CT coastal area. It means my temps. drop to -10 at worst (usually only with wind chill).
In terms of climate change (global warming is too narrow a moniker), scientists continue to analyze weather data and over time, well after it's too late to change our habits, they will be able to definitively tell us if our climate did, in fact, change. Meanwhile, because scientists are a cautious, methodical bunch in a world where "theories" take decades to develop, we have been tricked by those who wish to maintain the status quo into thinking that Climate Change is a theory like the Grassy Knoll theory or a theory on why choosy moms choose Jif. And so the public can feel justified to dither away, racking up debt to drive gas guzzling autos, eat 3000-mile salads and accumulate loads of plastic crap from China. But I digress...
In practical terms, think about the coldest nights you've had in the last 10 years. Was it very' cold? If the answer is yes, then insulate.
