Climate Change Fatigue? How to Read the IPCC Reports

The Intergovernmental Panel on Climate Change, or IPCC, has been busy churning out report after report. Rather than tuning out, we should be reading closely.

Forty-four years after the first Earth Day in 1970 (when I was a teenager and the Earth Day Coordinator in my junior high school), a lot has been accomplished in the U.S.: cleaner water, cleaner air, and more protections for endangered plants and animals.

But it can be hard to take in those successes when the looming crisis of climate change is ever more obvious—even as climate-science deniers and the well-paid politicians they invest in create an impression in the media that there remains significant debate about global warming.

Climate change threatens the environmental gains we’ve realized since the 1970s with far greater environmental catastrophe over the coming decades and centuries. The IPCC (Intergovernmental Panel on Climate Change) has recently released its three-part Fifth Assessment Report—the most definitive to date in describing what we can expect and what we are already experiencing with climate change.

Understanding IPCC

IPCC and its periodic reports can be pretty confusing, especially for acronym-challenged individuals like me, so let me provide a bit of background: IPCC was established by the United Nations Environment Programme (UNEP) and the World Meteorological Organization (WMO)—another United Nations agency—in 1988 to better understand climate change, what its impacts might be, and what to do about it.

The IPCC released its first Assessment Report two years later, in 1990. Like the subsequent Assessment Reports, this was really three reports from three different Working Groups:

• Working Group I assesses the physical scientific aspects of the climate system and climate change.

• Working Group II assesses the vulnerability of socio-economic and natural systems to climate change, negative and positive consequences of climate change, and options for adapting to it. This group focuses both on sectors (water resources, ecosystems, food and forests, coastal systems, industry, human health) and regions (Africa, Asia, Australia and New Zealand, Europe, Latin America, North America, Polar Regions, Small Islands).

• Working Group III assesses options for mitigating climate change by limiting or preventing greenhouse gas emissions and enhancing activities that remove them from the atmosphere.

An expanding series of IPCC reports

Since the first Assessment Report in 1990, Supplemental Reports were published in 1992 by Working Groups I and II; the Second Assessment Report was published in 1995; the Third in 2001; the Fourth in 2007; and the Fifth Assessment Report was released in three phases starting in September 2013.

If you’ve seen the IPCC report mentioned in the news and are wondering what’s what, here’s the breakdown of this Fifth Assessment Report:

• The Working Group I Report, “Climate Change 2013: The Physical Science Basis” (1,535 pages!), was released in September 2013 in Stockholm.

• The Working Group II Report, “Climate Change 2014: Impacts, Adaptation, and Vulnerability,” was released in March 2014 in Yokohama, Japan.

• The Working Group III Report, “Climate Change 2014: Mitigation of Climate Change,” was released in April 2014 in Berlin.

• A Synthesis Report of the Fifth Assessment Report will be published later this year.

In addition to these main reports, IPCC has published nine special reports over the years, including Renewable Energy Sources and Climate Change Mitigation (2011), Managing the Risks of Extreme Events and Disasters to Advance Climate Change Adaptation (2011), and Carbon Dioxide Capture and Storage (2005).

IPCC reports as a basis for policy

The ongoing IPCC reports have provided the foundation for important policies at an international level.

Starting in 1990, when the first IPCC Assessment Report was published, the UN General Assembly decided to initiate negotiations on how to regulate greenhouse gas emissions, and in 1992, the United Nations Framework Convention on Climate Change (UNFCCC) was opened for signatures at the UN Conference on Environment and Development in Rio de Janeiro, Brazil.

By 1996, IPCC had published comprehensive guidelines that countries could use in carrying out detailed greenhouse gas inventories, and these formed the basis of the UNFCCC Kyoto Protocol, which was adopted a year later and went into effect in 2005.

Ever more certain science, but stalling policy action

Each subsequent IPCC Assessment Report, especially the most recent, has painted a clearer and more detailed picture of what is happening to the Earth’s climate and the human causes of those changes.

Unfortunately, where the early reports included a range of impacts we could expect, reality has demonstrated the high end of the range. In other words, the scientists in IPCC have been shown to be conservative in their projections of the severity and speed of climate change.

In the Working Group I report from the Fifth Assessment Report, global mean temperatures by 2100 are now expected to be 6.7°F–8.6°F (3.7°C–4.8°C) higher than pre-industrial levels—up significantly from those in the early Assessment Reports. Already, an increase in global temperature of 1.1°F (0.61°C) has been measured.

A preview of coming attractions

The Working Group II report concluded with “very high confidence” that “impacts from recent climate-related extremes, such as heat waves, droughts, floods, cyclones, and wildfires, reveal significant vulnerability and exposure of some ecosystems and many human systems to current climate variability.”

The impacts of climate-related extremes, according to this Working Group II report, will include “alteration of ecosystems, disruption of food production and water supply, damage to infrastructure and settlements, morbidity and mortality, and consequences for mental health and human well-being.”

In the midst of this tangle of UN agencies and reams of reports, words like that make this Earth Day veteran stop and take notice.