Leslie Wyn Evans, Canada:
"While there are so many places in the world that qualify for this category, it is surprising how much change has occured in places that never had problems in the past.
"This is a picture of our back lawn in winter.
"As you can see, we now have enough water to qualify as a lake in winter - although it is lawn in summer.
"The good part is that the water table ensures that we always have green grass."