For the open square, a regular grid of telephone poles with staggered height sheets of white canvas or translucent plastic. This allows unobstructed air circulation while blocking 50% to 80% of the sun's heat.

For passive ventilation, 4 tall telephone poles arraigned in a square with transparent plastic sheets forming a square chimney. Inside the chimney have sheets of black plastic forming an X between the poles. The sun's heat on the black plastic will cause an updraft that will draw cooler air into the square through the gaps between the staggered height tents. There should be a number of chimneys arraigned around the square to provide enough draft to handle the heat generated by the people in the square [10,000 people = 1-5 megawatts].

Water hoses can be strung between the tent poles with mist sprinklers spraying the people in the square.

The temperature may be 111F outside but it will be less than 90F under the shade of the tents.

The easiest way to legally protect your personal info is to get congress to pass a law to make personally identifiable info joint property between the the person who is identified and the collector of the info.

Then, the holder of personal info will need your explicit consent in order to legally sell your info. You would need to voluntarily sell your ownership interest in the info to loose legal control of it. All of the normal property laws would take effect.

I worked 25 years as a Systems Programmer and Software Engineer before I finished my B.S. in Computer Science. Experience and allways having a job when you look for another job are the keys to working in the software field.