In what ways are humans effecting the environment in ways that only “nature” could in the past?

Question

One argument that I always hear from the climate change “deniers” is the fact that that climate change has had natural changes in the past. (And by their reasoning, because something also has natural causes, then it is beyond mankind’s ability to have any effect.)

However, just because something has had natural causes in the past, doesn’t mean that only natural causes are possible. Today, humans are able to influence the environment in ways that only nature could do in the past. Just off of the top of my head, some example are: forest fires, deforestation, reforestation, strip mining that levels whole mountains, the extinction of plants and animals, changing the flow of rivers through embankments and dredging, habitat loss for specific species, etc, etc…

What are some other examples?

Answer 1

A couple other examples are causing global cooling (aerosol emissions), changing the composition of the atmosphere (i.e. increased CO2, decreased ozone concentrations), and acidification of oceans.

Answer 2

The fundamental point to bear in mind is that the theory, which I believe is largely correct, is that the amount of carbon dioxide and methane released into the atmosphere has changed the energy balance of the earth.  Less energy is being radiated back to space and more is being absorbed in the earth.  This is what is new.  In theory the earth would now warm up to a point where balance would be achieved between the radiation falling on the earth and that being radiated from it. I don't think anyone knows even approximately at what temperature this equilibrium would be,

Answer 3

Badger Baiting!!

Answer 4

if you take Forrest fires in to the equation, we start them so doe's nature,why? nature through lightning on the plains of Africa, America, and Australia, and humans by not putting out camp fires and careless discarding of cigarettes etc,?

Answer 5

Stinky Badger Baiting???