Integrating Physics & Geography? Learning about temperature & pressure

[teachingquotient]

Frequent questions asked in IX std. geography class - CBSE-India:

1. Why should temperature & pressure correlations be different in geography and physics?
2. Why is earth called an open system? Or is it a closed system??  
3. Why isn't the geography teacher using scientific language while explaining temperature & pressure relations?

National Geographic Education for Teachers & Informal Educators :  http://education.nationalgeographic.co.in/education/ie/?ar_a=2 

Geophysics : http://en.wikipedia.org/wiki/Geophysics#Fluid_dynamics

Anybody to answer??