Field observations (e.g. glacial melting, CO2 levels, methane levels) tend to be wildly underestimated by the forecasting systems of a few years ago. Resource based systems dynamics simulations tend to predict collapse about 2030. We are seeing a species die-off worldwide both in terms of flora and fauna. Fishery collapse, measured by catch-size, is predicted to occur about 2048. David Wallace-Wells's The Uninhabitable Earth: Life after Warming is a frightening summary of what we can expect and is probably not too out-of-date.

In ten years everyone, even current climate change deniers, will be fighting to survive in a much changed world; in thirty, humans may be possibly have gone extinct, or be well on the way to being so.