Cloud formation changes the albedo of the atmosphere and influences patterns of precipitation, that in turn influence surface hydrology. Therefore cloud formation affects regional climate. Which of the following is NOT true of cloud formation? (choose both correct answers)
a. Rising air is associated with atmospheric low pressure systems and cloud formation
b. Cold fronts cause rapid vertical thunder cloud formation & strong winds associated with storms that bring abundant precipitation
c. Clouds form when air temperature decreases &/ or moisture levels increase
d. Clouds are made of only pure ice crystals
e. Due to evaporation clouds contain a higher proportion of 018 than 016 oxygen isotopes
f. Warm fronts cause clouds to form when a warm air mass slides over cold air relatively slowly (relative to a cold front)
g. Raindrops form when cloud droplets accrete on to aerosols until the water droplet is large enough to fall under the influence of gravity