As you move across a period the electrons are being added to the same shell. But, protons are being added as well. This makes the nucleus more positively charged and, increasing protons has a greater effect than electrons. So, there is a greater nuclear attraction and, because the electrons are being added to the same shell that shell gets pulled in more. This causes a decrease in atomic radius.
There is a ozone layer because of the special atomphere and chemical conditions that takes place there. I think the consequences of that home area is the very low winter temperatures.
