You didn't post any causal explanation, just correlation.
Assuming the correlation was significant, maybe low magnetic fields along the radar are responsible, or transient spikes, high frequency (dys-)harmonics - because it says "pulsed" but I don't know whether it means square pulse or rather probably not. Might latvias Equip is slightly out of tune, who knows. Noisy relais is no rarity at all.
Before conducting controlled experiments (which can verify causality) it's usual to conduct compared studies, which find the experimental factor occuring in a population and study its outcome. It's enough to establish correlation, much cheaper, and you can do it today instead of waiting however long it takes for the experiment (years if you have to grow trees while exposing them to microwave radiation)
Trees are quiet good at scattering RF mostly do to the water in them, their density of leaves/needles and the random orientation that they grow in. This leads to significant attenuation of the signal even if it isn't absorbed by anything. It's also worth noting that dried wood is almost RF transparent.
Lol, freudian slip?
You didn't post any causal explanation, just correlation.
Assuming the correlation was significant, maybe low magnetic fields along the radar are responsible, or transient spikes, high frequency (dys-)harmonics - because it says "pulsed" but I don't know whether it means square pulse or rather probably not. Might latvias Equip is slightly out of tune, who knows. Noisy relais is no rarity at all.