I went for a walk, of course, in the fantastic cold and brilliantly clear post-snow Central Park today. Here's a picture that gives you an idea of the glory of the day.

Now here's a contrasting picture, of a popular sledding hill, in the shadow of 157 W 57th St, the first of the new skyscrapers to go up on the south end of the park.

You can see how dramatic the difference is on a sunny day.

This shadow is emerging as a political issue in NYC.