Sea Reaver Barbarian: Eyes of the Storm in the fog?

[Gwen Smith]

I'm playing a Sea Reaver Barbarian archetype (from Ultimate Combat) in Skull and Shackles, and I'm trying to get some clarification on the Eyes of the Storm ability:

Eyes of the Storm (Ex):

At 2nd level, a sea reaver ignores any concealment provided by fog, rain, sleet, mist, wind, or other weather effects that is less than total concealment, and any penalties weather applies on Perception checks are halved.

This ability replaces uncanny dodge.

Now, the description of fog under weather effects says "Whether in the form of a low-lying cloud or a mist rising from the ground, fog obscures all sight beyond 5 feet, including darkvision. Creatures 5 feet away have concealment (attacks by or against them have a 20% miss chance)."

So I have two questions:
1) How exactly does Eyes of the Storm work in fog? How do you "halve a penalty" when the penalty is "obscures all sight"?

2) How do you think this ability would interact with spells like Fog Cloud, Obscuring Mist, etc.?

Fog Cloud:

A bank of fog billows out from the point you designate. The fog obscures all sight, including darkvision, beyond 5 feet. A creature within 5 feet has concealment (attacks have a 20% miss chance). Creatures farther away have total concealment (50% miss chance, and the attacker can't use sight to locate the target).

Obscuring Mist:

A misty vapor arises around you. It is stationary. The vapor obscures all sight, including darkvision, beyond 5 feet. A creature 5 feet away has concealment (attacks have a 20% miss chance). Creatures farther away have total concealment (50% miss chance, and the attacker cannot use sight to locate the target).

A moderate wind (11+ mph), such as from a gust of wind spell, disperses the fog in 4 rounds. A strong wind (21+ mph) disperses the fog in 1 round. A fireball, flame strike, or similar spell burns away the fog in the explosive or fiery spell's area. A wall of fire burns away the fog in the area into which it deals damage.

I'm thinking of these two spells in particular because the effect is described as "a bank or fog" and "a misty vapor" rather than "a magical fog" or "a magical mist". I don't think Eyes of the Storm would provide any benefit against magical weather-like effects, but I'm not sure if these two spells are just magical control of a natural weather effect. For comparison, I thinking of the difference between Control Winds (magical control of a natural weather effect) and Wind Wall (magical effect that mimics a weather effect), and I'm wondering if a similar distinction applies to these spells.

[Glutton]

1) See fine 5 feet away, no miss chance. The rest of the text does not apply (its for rain and such -4 to perception and such)

2) sames as above, it doesn't care that the fog is natural or magical, both are fog.

[Umbranus]

The text about halving penalties is for things like:

Ice storm wrote:

For the remaining duration of the spell, heavy snow and sleet rains down in the area. Creatures inside this area take a -4 penalty on Perception skill checks