1__ Vertical inequality = inequality among individuals or households (often differentiated economically). _
2__ Horizontal inequality = inequality among groups, typically by race, gender, ethnicity, religion or place of birth (often at a similar economic level but are differentiated due to cultural factors).
So why are climate inequalities often both? Because, for example, women will suffer from climate change more than men. Or because a community might be a cross representation of all people and affected by a major event but those who are white have other resources, networks and opportunities to fall back on whereas the people of color in that community may (statistically) not, widening the gap even further. Communities of color are always disproportionately impacted. Or the fact that rural communities are more exposed to the impacts of climate change than urban areas. _
Climate justice understands the connection between these and works on the knowledge that these inequalities exist within all countries and between them.