{
  "url": "https://fahrplan.events.ccc.de/rc3/2020/Fahrplan/events/11361.html",
  "id": 11361,
  "guid": "5f8b1e49-59ac-442e-8515-34ed300b1504",
  "logo": null,
  "date": "2020-12-30T12:40:00+01:00",
  "start": "12:40",
  "duration": "01:00",
  "room": "rC1",
  "slug": "rc3-11361-climate_tipping_points",
  "title": "Climate Tipping Points",
  "subtitle": "",
  "track": "Science",
  "type": "Talk",
  "language": "en",
  "abstract": "Politicians, economists and even some natural scientists have tended to assume that tipping points in the Earth system \u2014 such as the loss of the Amazon rainforest or the West Antarctic ice sheet \u2014 are of low probability and little understood. Yet evidence is mounting that these events could be more likely than was thought, have high impacts and are interconnected across different biophysical systems, potentially committing the world to long-term irreversible changes.\r\n\r\nThis talk summarizes evidence on the threat of exceeding tipping points and explores the effects of such large-scale changes, how quickly they might unfold and whether we still have any control over them.",
  "description": "The Intergovernmental Panel on Climate Change (IPCC) introduced the idea of tipping points two decades ago. At that time, these \u2018large-scale discontinuities\u2019 in the climate system were considered likely only if global warming exceeded 5\u2009\u00b0C above pre-industrial levels. Information summarized in the two most recent IPCC Special Reports (published in 2018 and in September 2019) suggests that tipping points could be exceeded even between 1 and 2\u2009\u00b0C of warming (see \u2018Too close for comfort\u2019).\r\n\r\nIf current national pledges to reduce greenhouse-gas emissions are implemented \u2014 and that\u2019s a big \u2018if\u2019 \u2014 they are likely to result in at least 3\u2009\u00b0C of global warming. This is despite the goal of the 2015 Paris agreement to limit warming to well below 2\u2009\u00b0C. Some economists, assuming that climate tipping points are of very low probability (even if they would be catastrophic), have suggested that 3\u2009\u00b0C warming is optimal from a cost\u2013benefit perspective. However, if tipping points are looking more likely, then the \u2018optimal policy\u2019 recommendation of simple cost\u2013benefit climate-economy models aligns with those of the recent IPCC report. In other words, warming must be limited to 1.5\u2009\u00b0C. This requires an emergency response.\r\n\r\nIn our view, the clearest emergency would be if we were approaching a global cascade of tipping points that led to a new, less habitable, \u2018hothouse\u2019 climate state. Interactions could happen through ocean and atmospheric circulation or through feedbacks that increase greenhouse-gas levels and global temperature. Alternatively, strong cloud feedbacks could cause a global tipping point.\r\n\r\nThis talk will give an overview on how these different scenarios might play out, how likely they are, and what we need to do to avoid them.",
  "recording_license": "",
  "do_not_record": false,
  "persons": [
    {
      "id": 1943,
      "public_name": "Stefan Rahmstorf"
    }
  ],
  "links": [],
  "attachments": [],
  "room_id": "973ec154-a5b5-40ac-b4e8-b74137f647e8",
  "origin": null
}