I just changed the header picture of this blog. My camera captured the myriad of footprints going out onto the ice of a lake nearby. It got me thinking—about what might happen if things warm up so much so that the lake here no longer freezes.

For me, a California girl, it is almost a freak of nature; to be able to walk on water is both scary and incredibly exciting. I only experienced it for the first time in my life just three years ago. Extreme cold is part of life here in the far north. Food, culture and recreation have evolved to endure but also take advantage of this so-called winter half of the year.

For example, every February, when possible, thousands of long distance ice skaters glide the 80 kilometers from Uppsala to Stockholm. It is amazing to watch men with icy mustaches, spots of blood from the inevitable spills resulting from skating on an imperfect surface and tired legs pass by silently, focusing on the next placement of a skate.

Yesterday I saw a couple out fishing on the ice. They drilled a hole and parked their chairs down beside it, fishing lines dangling down below the frozen layer.

For two years in a row I have participated in an annual week’s worth of cross-country skiing events of distances between just a few kilometers for children and a 90-kilometer-long race, the Vasaloppet. It is one of the oldest and longest races of its kind.

Kids grow up on ice skates, ours partaking in this activity at school twice a week during the coldest months. The soccer field across the street from their school is flooded after Christmas when the temperatures stay below zero. (It is no wonder the Nordic countries do so well at the Winter Olympics.)

In other parts of Scandinavia frozen lakes serve as a shorter route to destinations on the other side of any large body of water. In a good winter you can just drive, snow mobile or ski over it.

But more importantly, some rely on ice to survive. We have all seen the pictures of polar bears hunting from the ice. Polar bears hunt primarily at the interface between ice, water, and air; they only rarely catch seals on land or in open water. Yet our lifestyles, our carbon footprints, are endangering their habitat, not only because of global warming but also, I fear, due to the increasingly accessible natural resources, like oil and gas, that are found in the Arctic. Their extraction poses a great threat to the incredible animal life, local peoples and pristine beauty.

We are all leaving our footprints, some wider than others. Each one of us has an impact, and it is something we can adjust. So today, to reduce my footprint, I am going to make a vegetarian dinner. I am going to take the train or walk instead of starting up the car and I will abstain from purchasing all nonessential items.

I encourage you to do something too so we can continue to enjoy all the wonders that winter brings!