Hi Frank. It’s great that you are making observations about snow. It’s difficult to find out anything interesting about a snow sample outside of a laboratory. Instead of focusing on what else is in the snow, like microplastics or black carbon, you could measure changes in snow depth and density over time. When snow first falls, you can measure its depth with a ruler. If you then cut out a section (be sure to record the volume of it!) you can melt it and weigh the water. The weight of the water divided by the volume of the snow tells you its density. Both the depth and density of snow are changing with the climate so you could look at how these change over time if you are interested.