A Look at Climate Change and the IPCC as the U.S. Re-enters the Paris Agreement

Climate change is one of the most serious global problems today. Increasing temperatures, rising sea levels, acidification of the ocean, damaging hurricanes, droughts, wildfires and other extreme events have caused devastating human, environmental and economic damage. In response to escalating climate change concerns, the International Panel on Climate Change (IPCC) was created in 1988 by the World Meteorological Organization (WMO) and the United Nations Environment Programme (UNEP). The mission of the IPCC is to provide the world’s governments with sound scientific information on climate change relevant to the development of policies to mitigate greenhouse gas emissions and adapt to the impacts of climate change.

The IPCC was awarded the Nobel Peace Prize in 2007 for its “efforts to build up and disseminate greater knowledge about man-made climate change, and to lay the foundations for the measures that are needed to counteract such change.”

Mike Kennish
Michael Kennish, professor emeritus in the Department of Marine and Coastal Sciences

Thousands of scientists and other experts from around the world volunteer, under the leadership of the IPCC, to examine the science of climate change, its impacts and approaches to reducing emissions. Since 1988, the IPCC has released five major Assessment Reports on climate change (1990, 1995, 2001, 2007 and 2014) and numerous special reports.  

Rutgers alumnus Hoesung Lee, who graduated with a doctoral degree in economics in 1975, serves as the current chair of the IPCC, which has spent nearly four years preparing its Sixth Assessment Report. This report will come out in three volumes – addressing the physical science of climate change, climate impacts and adaptation, and climate change mitigation – and an integrative synthesis report. The first volume, on the physical science, will be released this summer. The final two volumes and the synthesis report will be released in 2022. In the course of its Sixth Assessment cycle, the IPCC has also produced three special reports, covering the land, the oceans, and the challenge of limiting global warming to 1.5°C.

Bob Kopp
Robert E. Kopp, professor and director of the Rutgers Institute of Earth, Ocean, and Atmospheric Sciences.

On February 19, the U.S. will re-enter the Paris Agreement, from which it withdrew on November 4, 2020. This landmark agreement, which was adopted by 196 countries and came into force on December 4, 2016, created a unifying international platform for nations to combat climate change and its devastating effects. A major long-term goal of the Paris Agreement is to limit the increase in global average temperature to well below 2.0°C (3.6°F) above pre-industrial levels, and preferably to limit the temperature increase to no more than 1.5 °C (2.7 °F). To this end, member nations have pledged to reduce their greenhouse gas emissions and to submit a strategy to accomplish these reductions.

The approaching date of the U.S. reentry into the Paris Agreement prompted the SEBS/NJAES Newsroom to learn more about the IPCC, the process of assembling its landmark Assessment Reports and some of the key strategies for tackling climate change. Multiple Rutgers faculty members have played important roles in the IPCC, including several who served as authors or reviewers of earlier reports that, in part, led to the Nobel Peace Prize for the IPCC in 2007. For the current assessment cycle, Kevon Rhiney, assistant professor in the Department of Geography, was a contributing author on the Special Report on Global Warming of 1.5°C, which was published in 2018. Pamela McElwee, associate professor in the Department of Human Ecology, was a lead author on the Special Report on Climate Change and Land, which was published in August 2019.

Providing some answers are Michael Kennish, professor emeritus in the Department of Marine and Coastal Sciences, who serves as an expert reviewer for the current assessment cycle, and Robert Kopp, director of the Rutgers Institute of Earth, Ocean, and Atmospheric Sciences (EOAS) and a professor in the Department of Earth and Planetary Sciences, who is a lead author of the Sixth Assessment Report.

What is the role of the IPCC and why is such a body important?

Kennish: The role of the IPCC is to prepare comprehensive Assessment Reports, Special Reports, and Methodology Reports on climate change. The Assessment Reports provide the latest scientific, technical, and socio-economic information on climate change, as well as its causes, impacts, risks, and options for adaptation and mitigation. The Special Reports assess specific issues of concern on climate change, and the Methodology Reports offer practical guidelines for the preparation of greenhouse gas inventories. These reports collectively are critically important because they document the state of climate change and update the conditions worldwide at periodic intervals of time. Policymakers in governments have access to the current state of climate change and projected conditions based on IPCC assessment of the latest climate change information prepared by experts around the world. The policymakers play a vital role in forging plans and policies that effectively address societal problems of climate change at local, regional, and national levels.

Since 1988, the IPCC has gone through five assessment cycles and delivered five Assessment Reports to member states. Can you explain the process and what’s involved in gathering and analyzing what must be a staggering amount of scientific material.

Kennish: I will discuss the preparation of the Assessment Reports since they are the most comprehensive reports prepared on climate change by the IPCC, covering a wide range of disciplines. Preparation of the reports follows approved IPCC procedures. The goal is to produce reports that achieve the highest standards of scientific excellence, and balance. A comprehensive description of the process of preparing Assessment Reports can be found in the Procedures for the Preparation, Review, Acceptance, Adoption, Approval, and Publication of IPCC Reports. I will briefly summarize the salient points of the process.

There are three IPCC Working Groups and a Task Force involved in the preparation of the Assessment Reports. These include: (1) Working Group I, which deals with the physical science basis of climate change; (2) Working Group II, which deals with climate change impacts, adaptation, and vulnerability; and (3) Working Group III, which deals with mitigation of climate change. The Task Force focuses on national greenhouse gas inventories and reduction. A Summary Report is also prepared. The IPCC does not conduct basic research on climate change.  Its role is to assess relevant scientific, technical, and socio-economic literature on the subject.

Assembling authors, editors and reviewers as experts for the preparation of Assessment Reports requires careful planning. IPCC member governments and observer organizations nominate prospective authors and editors for the report preparation based on their expertise and the range of scientific, technical, and socio-economic areas to be covered. Experts are selected from different regions and countries (developed and developing countries) to avoid bias and to achieve appropriate geographic diversity. Expert reviewers are considered by the IPCC based on their relevant expertise.

Numerous scientists volunteer their time without compensation to review thousands of published scientific articles each year to assess the status of climate change for the Assessment Reports and to ensure an objective and thorough review process. To this end, multiple drafts of the reports are prepared, reviewed, and revised. Lead authors and contributing lead authors draft the report chapters and revise them, responding to comments by reviewers. Review editors work with the author teams to ensure that the authors consider reviewer comments in their drafts. The author teams prepare First Order Drafts and Second Order Drafts of the Assessment Reports taking into account peer-reviewed and non-peer reviewed literature on climate change. The authors concurrently prepare a Summary for Policymakers, which is a document of the main policy-relevant components of the Assessment Reports. Expert reviewers from around the world comment on the draft reports for accuracy and completeness. As an expert reviewer, I have reviewed nearly a thousand draft report pages. Governments and observer organizations can comment on the draft reports as well. The authors consider these comments for revision of the reports.

The authors prepare final drafts of the Assessment Reports and Summary of Policymakers after the second stage of review. The Summary of Policymakers is part of the Synthesis Report, written in non-technical language by the authors. The final drafts are also subject to review by governments, which can provide additional comments.  An IPCC panel and responsible Working Groups or Task Force must then formally endorse the IPCC reports before they can be released.  There are three levels of endorsement: (1) Approval; (2) Adoption; and (3) Acceptance. First Order Drafts and Second Order Drafts of the Assessment Reports are made publicly available after the final reports are published.

The IPCC is in the current assessment cycle for the Sixth Assessment Report. When is that due and what is your role?

Kopp: I am one of the 15 lead authors of the chapter in the Sixth Assessment Report on the ocean, cryosphere and sea-level change. Along with our three coordinating lead authors, we have worked intensively since summer 2018 years to assess what’s new in the scientific literature since the Fifth Assessment Report was published in 2013. Our chapter focuses on topics such as changes in the oceans, change in ice sheets and glaciers, and sea-level change. I’ve particularly focused on the parts of the chapter related to past and future sea-level changes. Gregory Garner, a Rutgers assistant research professor collaborating closely with me, has worked as a chapter scientist to develop a computational framework for integrating the chapter assessments of the different drivers of sea-level change to produce projections of future global and regional sea-level changes.

The report schedule got shifted back a bit due to the pandemic. The Working Group 1 report, of which our chapter is part, is now scheduled for release in August.

While the sheer scope of the field of climate science is daunting and constantly evolving, there must be some facts that are broadly and universally agreed on in the scientific community. What are those?

 The basic story has been well established over the last several decades by the scientific community and by past IPCC reports, as well as by other reports such as the U.S. National Climate Assessment, and it can be presented very simply. Climate change is happening now, it is having costly impacts on global society, and it will continue to get worse with every ton of carbon dioxide emitted. The only way to stabilize the global climate is to bring net global carbon dioxide emission to zero; and even then, there will remain impacts to which people and ecosystems will have to adapt.

One of your primary areas of focus is on sea-level change. As a coastal state, what would you say are the most important priorities for New Jersey with respect to preparing for a future event like Superstorm Sandy?

Kopp: Climate change unequivocally made Superstorm Sandy’s impacts more severe because the storm came on top of sea levels several inches higher than they would have otherwise been, exposing close to 100,000 additional people in New Jersey and New York to flooding. In general, climate change is also projected to make hurricanes like Sandy more intense. The growing hazard from coastal storms is one of many climate impacts that we have to reckon with.

There are two basic strategies for tackling climate change: reducing its magnitude by stabilizing the climate, and making our communities more resilient to the changes that nonetheless occur.

Our number one priority should be a whole-hearted engagement with the challenge of stabilizing our global climate by bringing net global greenhouse gas emissions to zero. Federal policy, state policy, and even University policy need to be directed toward that end. I’m pleased that President Biden and Governor Murphy have made tackling climate change a priority, and I hope the New Jersey will increase its ambition by setting a net-zero target emissions no later than the 2050 target that President Biden has set. Here at Rutgers, my co-chair Professor Kevin Lyons and I have been working with numerous faculty, staff, and students over the last year and a half to develop a strategy for the University to do our part.

Our second priority must be making sure that growing hazards produced by climate change are integrated into land-use planning and other planning processes, and that support is provided to ensure that climate adaptation doesn’t come at the expense of the most vulnerable. New Jersey has laid out an ambitious policy vision for a statewide climate change resilience strategy, which is now in development, and a bill signed just this month requires municipal master plans to incorporate hazard projections.

But integrating climate change into decision processes requires developing a workforce of ‘climate translators’ who are fluent with language of both climate science and local decision-makers. Doing so, without further disadvantaging the less wealthy, demands that this be a public workforce. I believe that public and land-grant universities have a particularly important role to play, both in developing the workforce and in helping bridge science and community decision-making. Here again, I think Rutgers has made some important and pioneering steps, through initiatives like our graduate training programs in Coastal Climate Risk and Resilience and through the state-funded New Jersey Climate Change Resource Center. Such efforts will have to be scaled up to meet the needs of communities throughout our state and linked to comparable efforts by other universities to meet the scale of the national and global problem.

This article was originally posted by the NJAES/SEBS Office of Communications and Marketing on February 19, 2021.