What's worse: fluctuating Temp or Humidity?

[Jamieboy]

I've fairly recently purchased what (to me, at least) is my first really nice bass - a Sandberg TT4. 

 

My somewhat obsessive nature coupled with how much I'm loving the instrument has got me thinking about how and where I keep it. I basically have two options:

 

1. In a garden office I have. The building is insulated and has heating but we only use the heating when the building is in use so it will definitely be getting cold in there at night etc. I.e. environment where temperature probably fluctuates a fair bit.

 

2. Upstairs at home - with me and the wife taking showers in the morning and the kids having a bath in the evening. I.e. environment where probably humidity fluctuates a fair bit. 

 

Imagine it's all a question of fact and degree, but out of interest just wondered if there was any thoughts about this.

[Hellzero]

In the garden office in its case or gigbag will protect it from humidity and temperature changes.

[itu]

Do not place the bass to direct sunlight. UV will change the colour and the temp difference can be substantial.