Oh dear.  What a complete load of pseudo-scientific bunkum.  And not just one particular bit, all of it.  

Oh, except that microwaves can heat water - it's how microwave ovens work - but the intensity and power of microwave radiation in the atmosphere is minuscule - probably around a millionth-millionth the level in a microwave oven, and I could still be overestimating by a similar amount.

Consider this - a microwave oven emits around 500 to 1000 watts of microwave energy, enough to boil a glass of water in a minute or two.

In comparison, a cellphone radio signal is so incredibly weak, that the only thing that makes this technology even possible is our ability to fabricate very low noise radio frequency amplifier devices. Even the totality of cellphone base stations around the globe would be dwarfed by the amount of energy in just one second of solar radiation.

And earth's magnetic field is not rotating.  It's aligned with the Earth's axis, although it does wobble a bit.