So instead of causing seasons, the changing distance from the sun actually lessens the severity of northern hemisphere winter caused by earth's tilt, and heightens the severity of southern hemisphere summer.
(the changing distance from the sun; actually lessens; the severity of northern hemisphere winter) (northern hemisphere winter; caused; by earth's tilt) (the changing distance from the sun; heightens; the severity of southern hemisphere summer)
the changing distance from the sun northern hemisphere winter the changing distance from the sun
actually lessens caused heightens
the severity of northern hemisphere winter
by earth's tilt
the severity of southern hemisphere summer