Upper-atmospheric nuclear explosions fry satellites by creating artificial radiation belts. Discovery of "The Christofilos Effect" was made during Operation Argus: whistler waves scrape radiation from space and dump them on the poles creating artificial aurora.
The Partial Test Ban Treaty (PTBT) is the abbreviated name of the 1963 Treaty Banning Nuclear Weapon Tests in the Atmosphere, in Outer Space and Under Water, which prohibited all test detonations of nuclear weapons except for those conducted underground. The treaty, also commonly known as the Limited Test Ban Treaty (LTBT), had three main aspects: (1) prohibiting nuclear weapons tests or other nuclear explosions under water, in the atmosphere, or in outer space, (2) allowing underground nuclear tests as long as no radioactive debris falls outside the boundaries of the nation conducting the test, and (3) pledging signatories to work towards complete disarmament, an end to the armaments race, and an end to the contamination of the environment by radioactive substances. 
Signed after multiple upper-atmospheric (space-based) nuclear explosions:
- Operation Argus (USA): August 27 - September 6, 1958
- Operation Hardtack (USA): August 1-12, 1958
- Starfish Prime (USA): July 9, 1962
- Project K (Russia): October 22 - November 1, 1962
The Nuclear Test Ban Treaty (NTBT) and Comprehensive Nuclear-Test-Ban Treaty (CTBT) succeeded the PTBT for ratifying parties. The use of sounding rockets to modify space weather and ionospheric conditions began before and expanded exponentially following this ban.
If any of the links above do not work, copy the URL and paste it into the form below to check the Wayback Machine for an archived version of that webpage.