New IPCC Assessment Report: Climate change widespread, rapid, and intensifying

How has climate changed up until the present? How will it change in the future? Questions like these are answered in the recently published first part of IPCC´s Sixth Assessment Report, which summarizes the scientific facts about climate change. This first part will be supplemented with two more parts in the coming spring, addressing adaptation to potential impacts of climate change and its potential mitigation. A synthesis report of the three parts will be published in autumn 2022.

The Max Planck Institute for Meteorology (MPI-M) contributed to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC) with its extensive model calculations and contributions from numerous scientists. MPI-M Director Prof. Jochem Marotzke is coordinating lead author of the chapter “Future global climate: scenario-based projections and near-term information”. In addition, he worked on the summary for policy makers. Prof. Dirk Notz, MPI-M and Universität Hamburg was lead author on chapter 9 "Ocean, cryosphere and sea level change". MPI-M scientist Prof. Victor Brovkin worked on the report as a review editor in the for Chapter 5 "Global carbon and other biogeochemical cycles and feedbacks." Prof. Torsten Mauritsen, now Stockholm University, was lead author on Chapter 7, "The Earth's energy balance, climate feedbacks and climate sensitivity."

 

It is clear: humans have warmed the climate.

 

The main messages of the IPCC's Sixth Assessment Report confirm that the atmosphere and ocean have continued to warm over the past decade, snow and ice levels have continued to decline, and global sea level has continued to rise. Greenhouse gas concentrations have also continued to increase. To still meet the Paris climate goals, overall greenhouse gas emissions must be brought to zero.

 

Can the 1.5-degree target still be met? In all calculated scenarios, global warming in the early 2030s will exceed this mark with a probability of more than 50 percent. Prof. Jochem Marotzke: "If we want to keep within 1.5 degrees, two things must come together. First, emissions must be brought to net zero in the next 30 years, and second, the climate must not be too sensitive."

 

Prof. Dirk Notz uses the example of the Arctic to make clear how urgent it is to act decisively: "Until now, we have always said that we can still prevent the Arctic from becoming ice-free. Now, for the first time, we have the case that it is probably too late for that, and we can only limit the frequency of ice-free summers. To me, that's a sign of how far climate change has gone." He also explains that we have an impact on climate change with our choices: "The disappearance of ice is linear with temperature. That is, ice loss would be directly halted to the greatest extent possible once human greenhouse gas emissions and the warming that accompanies them are stopped. We are not passively at the mercy of climate change, we are controlling it. We still have the choice in which scenario we will end up."

Source: press release of the German Climate Consortium

 

Contact / Scientific Contacts:

To the chapters of AR6, WGI, Physical Basis

4 - Future global climate: scenario-based projections and near-term information:
Jochem Marotzke, Hauke Schmidt

5 - Global carbon and other biogeochemical cycles and feedbacks:
Victor Brovkin

9 - Ocean, cryosphere and sea level change:
Dirk Notz (MPI-M and Universität Hamburg), Johann Jungclaus

Email: firstname.lastname@mpimet.mpg.de
Phone numbers:      MPI-M: +49 (0) 40 41173 -

Brovkin, Victor, Prof.               339
Marotzke, Jochem, Prof.         311
Notz, Dirk, Prof.                       163
Schmidt, Hauke, Dr.                405
Jungclaus, Johann, Dr.            109

 

Communication:

Dr. Annette Kirk
Phone: +49 (0) 40 41173 374
Email: annette.kirk@we dont want spammpimet.mpg.de

Dörte de Graaf
Phone: +49 (0)40 41173 387
Email: doerte.degraaf@we dont want spammpimet.mpg.de

 

Background information:

  1. IPCC: www.ipcc.ch
  2. IPCC AR6 WG I: https://www.ipcc.ch/report/sixth-assessment-report-working-group-i/
  3. Model simulations of MPI-M for CMIP6:
    https://mpimet.mpg.de/en/communication/news/single-news/new-climate-simulations-for-the-coupled-model-intercomparison-project
  4. DKRZ - Climate Simulations for the IPCC Report - Coupled Model Comparison Project 6 (CMIP6): https://www.dkrz.de/en/communication/climate-simulations/cmip6-en/cmip6?set_language=e