The average annual level of atmospheric CO2 is increasing today. Glacial ice moves uphill during times of glacial retreat. Upper atmospheric ozone is created by lightning. Chlorofluorocarbons and methyl bromide breakdown in the upper atmosphere releasing Cl and Br, respectively, which in turn destroy ozone. Rising sea level causes barrier islands to shift their position landward.
Sea stacks represent erosional remnants following sea cliff retreat.
Marine terraces, such as those of Palos Verdes, are indications of uplift or lowering of sea level. The greater the angle of waves to shore, the greater the amount of longshore current. Sand accumulated on the north side of a groin indicates that the direction of longshore drift is from the north. Sea cliff retreat occurs by the combined forces of wave erosion and mass wasting. Plastic is the most abundant solid waste product washed up on beaches.