Keeping 1.5 C Alive: Responding to the IPCC Report on Mitigating Climate Change

Posted by Brad Johnson Tue, 12 Apr 2022 14:30:00 GMT

The Intergovernmental Panel on Climate Change (IPCC) Working Group III report underscores the urgency for rapid, deep and sustained cuts to greenhouse gases for the world to have a chance of limiting global warming to 1.5 degrees C (2.7 degrees F). This seminal report offers new insights on possible pathways for policymakers, business leaders and others to ramp up their efforts to tackle the climate crisis at the scale and urgency required.

Join World Resources Institute experts and IPCC authors on April 12 for an overview of the IPCC report and learn about the transformative actions across sectors (including energy, transportation, food, forests and much more) needed to curb greenhouse gas emissions and remove carbon dioxide from the atmosphere.

This event will be hosted in English with simultaneous interpretation in French and Spanish.

  • Chukwumerije Okereke, Director, Centre for Climate Change and Development, Alex Ekwueme Federal University Ndufu-Alike Nigeria; IPCC Coordinating Lead Author
  • Taryn Fransen, Senior Fellow, Climate, World Resources Institute
  • Craig Hanson, Vice President for Food, Forest, Water & the Ocean, World Resources Institute
  • Jennifer Layke, Global Director, Energy, World Resources Institute
  • Preety Bhandari, Senior Advisor, Global Climate Program and the Finance Center, World Resources Institute (Moderator); IPCC Lead Author

Register here

The consensus behind climate change science and the InterAcademy Council’s review of IPCC processes and procedures

Posted by Brad Johnson Wed, 10 Mar 2010 19:45:00 GMT

United Nations, UN Foundation will join with IPCC scientist to provide commentary on the announcement of a IPCC review panel and the state of climate science overall.

Telephone conference call to discuss the consensus behind climate change science and the context of the InterAcademy Council’s review of IPCC processes and procedures.

  • Chris Field, director, Carnegie Institution Department of Global Ecology, Stanford University
  • Janos Pasztor, director of Secretary-General’s Climate Change Support Team
  • Timothy Wirth, president, United Nations Foundation

US: 1-800-351-9742
Int’l: 1-334-323-7224

Code: IPCC2010

Learning from a Laureate: Science, Security and Sustainability

Posted by Brad Johnson Wed, 30 Jan 2008 14:00:00 GMT

This Wednesday, Chairman Edward J. Markey (D-Mass.) and the Select Committee on Energy Independence and Global Warming will host Dr. Rajenda Pachauri, Chairman of the Nobel Peace Prize winning Intergovernmental Panel on Climate Change, in his first appearance before Congress. Last year, under Dr. Pachauri’s leadership, the IPCC produced the seminal review of the science of global warming, its current and potential future impacts and the positive strategies available to help address this looming threat.

Dr. Pachauri will share his views on the urgency of addressing global warming and the issues Congress and other political leaders must consider when crafting climate legislation this year.

  • Dr. Rajenda Pachauri, Chairman, Intergovernmental Panel on Climate Change

Are 1990 Levels by 2020 a Sufficient Cut?

Posted by Brad Johnson Fri, 25 Jan 2008 17:47:00 GMT

The Lieberman-Warner cap-and-trade bill (S. 2191), which Sen. Boxer said may come to the floor before June, sets a cap of 15% below 2005 emissions levels by 2020 for covered sectors, reducing allowed emissions to the amount last seen in 1990.

Is that near-term target sufficient, in terms of the science?

As Holmes Hummel points out, the IPCC Fourth Assessment Report (AR4) paints a much different picture.

At Bali, all of the Annex I signatories to the Kyoto Protocol (every industrialized country other than the US and Turkey) agreed to this roadmap, which states in convoluted language that the Annex I countries “noted” that the AR4 indicates that global emissions “need to peak in the next 10-15 years” and be reduced “well below half of levels in 2000” by 2050 “in order to stabilize their concentrations in the atmosphere at the lowest levels assessed by the IPCC to date in its scenarios.” The countries also “recognized” that the AR4 indicates that to achieve those levels “would require Annex I Parties as a group to reduce emissions in a range of 25–40 percent below 1990 levels by 2020.”

25-40% below 1990 levels is dramatically below the Lieberman-Warner target. From AR4, these “lowest levels” of concentrations are 350-400ppm CO2.

What’s the value of achieving concentrations “at the lowest levels”? The report says that using the “best estimate” for climate sensitivity (the temperature response to greenhouse gas concentrations), reaching a stable concentration of 350-400ppm CO2 leads to 2.0-2.4 degrees C warming above pre-industrial levels. But Hummel notes that the “best estimate” is just one for which half the estimates are higher and half are lower.


To have a 50% chance of making the 2°C stabilization target, global emissions need to peak by 2015 and Annex I countries need to be 25-40% below 1990 by 2020.

As AAAS president John Holdren argued in his speech Meeting the Climate Challenge (at 38:29; see also the slide presentation):
The chance of a tipping point into truly catastrophic change grows rapidly for increases in the global average surface temperature more than about 2°C above the pre-industrial level, and again we’re already committed basically to one and a half. For a better than even chance of not exceeding 2°C above the pre-industrial level, CO2 emissions must peak globally no later than 2025 and they need to be falling steadily after that. That is a great task.
From the UN Scientific Expert Group on Climate Change and Sustainable Development, an international panel of 18 top scientists (including John Holdren):
In our judgment and that of a growing number of other analysts and groups, however, increases beyond 2°C to 2.5°C above the 1750 level will entail sharply rising risks of crossing a climate “tipping point” that could lead to intolerable impacts on human well-being, in spite of all feasible attempts at adaptation.