[Music] the impacts of climate change are now impossible to ignore but are there places that are immune or that climate change might even make nicer some experts say one of those places could be Duluth Minnesota but what's so special about this small Midwestern City and is it in fact climate proof the key to duluth's climate resilience is also the thing that makes it a very cold place Lake Superior it's the coldest and the deepest of all the Great Lakes and it's also the largest freshwater lake in the world by surface area and that surface area is what's really super impactful to weather and so when we think about just the mass quantity of water the mass quantity of space that it takes up it's just on a completely different scale and because of that it has that much larger of an influence one of the biggest impacts that it's going to have is on temperature here in the Summer Lake Superior acts like a big air conditioner essentially I think anybody who's been to Duluth in the in the summer is used to the idea that you might have some really glorious days and then the next day is really chilly and it's simply because we have this big reservoir of cold sitting right there and if the wind comes off the lake you're going to be experiencing some of that cold the reason that that's interesting is because the lake tends to lag even though summer conditions have reached us the lake might not have reached summer yet and that is largely due to the heat capacity of water versus Air and a way to think about heat capacity is kind of as memory so air has a shorter term memory or a smaller heat capacity and it can warm up pretty quick and cool down pretty quick versus water it takes longer to warm up as well as to cool down [Music] Lake Superior is a remarkably Cold Lake first of all it's actually a lot further north and sits in a much colder climate than the other Great Lakes the other really important aspect is that it's just really deep as a counter example Lake here is also a large lake but relatively shallow compared to Lake Superior almost 10 times shallower or one tenth is deep in that case the water temperatures basically keep up with air temperatures and you don't end up with those super cold winds blowing off of Erie in the middle of July or something like that but even though Lake Superior makes Duluth more resilient AS Global temperature changes it isn't immune to the effects the proof is in the data what we see are Trends towards warmer Summers the lakes are four to five degrees Fahrenheit warmer now in the summer than they were 40 years ago and a lot of that is driven by the fact that we are having much milder Winters which means less ice a lot of work that I've done in the past has suggested that ice cover in the winter is a very strong predictor of what happens the following summer as much as whether we're having a warm or cold summer and so it's a combination of milder Winters and warmer Summers that are causing Lake temperatures to be measurably and statistically warmer now than they were 40 years ago more ice in colder water mean a colder summer less ice will be followed by a warmer summer Lake Superior is one of the fastest forming Lakes on Earth we continue to see a decline in ice cover every single year with fairly large variations but still a decline overall and those have huge ramifications warming us up warming the Lakes up as well and how that influences the whole Hydro meteorological cycle that we have come to depend on we saw just last summer that we can fall into pretty serious drought in northern Minnesota and we can be impacted by wildfires that you know burn up and they affect our air quality and they affect our quality of life as well and there's absolutely no reason to think that Duluth will not be impacted by climate change but even if Duluth does see higher temperatures there's one thing that is not likely to change I think perhaps the more important aspect of Duluth as a climate Refuge is the fact that we have abundant water we're sitting on 10 of the world's fresh water right here water scarcity is not the same kind of issue here as it is in for instance the American southwest foreign