Q4.17. Which of the following statements about thresholds and abrupt climate change is false? 1There are thresholds in the climate system that, once crossed, can produce large, rapid changes.
2Positive feedbacks that amplify the effects of small changes can produce abrupt climate change.
3Climate proxies have recorded multiple examples of abrupt climate change in the past.
4Climatologists predict that reversing the effects of "tipping points" will usually occur rather quickly.