I really liked the “Animals in the Cold” lesson and would incorporate sensory play by placing penguins and polar bears in water and freezing them. I would set up these animals on a tuff tray and using water spray/water bottles, little tools the children would free the animals. We would then play with the animals as small world play and these could be two aistear stations. I think this would also be a good lead in to teaching about weather and on a very basic level lead the conversation in the direction of the ice caps melting.
On a separate note I absolutely love Astronomy picture of the day and have done for years since my uncle introduced me to it. I never thought about using it in the classroom!