September 25, 2019 – A new report released by the Intergovernmental Panel on Climate Change highlights the need for urgent, ambitious, and coordinated action to address unprecedented and enduring changes in the planet’s oceans and frozen components.  

The knowledge synthesized in the Special Report on the Ocean and Cryosphere in a Changing Climate (SROCC) also aims to facilitate the ability to adapt to ongoing, irreversible changes for over one billion people living in high mountain regions, low-lying coastal zones, small island developing states, and the Arctic region. 

“What we see is that human-induced climate change has a major footprint on the systems we depend on, from the top of the mountains to the depths of the ocean. These changes will continue for generations to come,” said Debra Roberts, Co-Chair of IPCC Working Group II and member of the Future Earth Urban Knowledge-Action Network Steering Committee. 

The message from this IPCC Special Report builds on those of other collaborative reports released this past week, such as United in Science, which calls for “immediate and all-inclusive action” to reach the Paris agreement. Meeting the 1.5 Climate Ambition declares that to reach this goal, it “will require the fastest economic transition in history.”

The Special Report on the Ocean and Cryosphere in a Changing Climate (SROCC), approved on September 24, 2019 by the 195 IPCC member governments, is a systematic review of the most recent literature, both published and in publication right now. It is the third in a series of Special Reports produced in the IPCC’s Sixth Assessment Cycle, following the Special Report on Climate Change and Land (SRCCL) released in August 2019 and the Special Report on Global Warming of 1.5°C released in October 2018.

For this report, more than 100 scientists from 36 countries – 19 of which are developing countries or countries with economies in transition – assessed almost 7,000 publications detailing the latest scientific knowledge about the physical science basis and impacts of climate change on ocean, coastal, polar and mountain ecosystems, and the human communities that depend on them. Members of Future Earth’s global research projects, knowledge-action networks, and partners contributed to the report in the role of coordinating lead authors, lead authors, and reviewers. 

The oceans make up 70 percent of the earth’s surface. The cryosphere (from the Greek “kryos,” meaning cold or ice), includes snow, glaciers, ice sheets and ice shelves, icebergs and sea ice, ice on lakes and rivers, as well as permafrost and seasonally frozen ground. Together these elements make up the majority of the Earth’s geography and significantly affect the Earth’s climate. 

Research has found the ocean is now warmer, more acidic, and less productive – having already absorbed more than 90 percent of the excess heat in the climate system. Melting glaciers and ice sheets are causing sea level rise, and coastal extreme events are becoming more severe.

Global warming has already reached 1°C above pre-industrial levels, due to past and current greenhouse gas emissions. The Special Report on Global Warming of 1.5°C released last year examined the significant differences of impacts on Earth systems, ecosystems, and people, for staying at or below 1.5°C compared with the 2°C goal set in the Paris Agreement. 

But the new report highlights several starkly different futures in ocean and frozen ecosystems in relation to this half degree change. All coral reefs are likely to collapse at 2 degrees – due to the frequency of marine heatwaves being 20 times higher at 2°C over pre-industrial levels and continued ocean acidification due to carbon uptake from the atmosphere – yet some have a chance of recovery at 1.5 degrees.

If global warming is stabilized at 1.5°C above pre-industrial levels, the Arctic ocean would only be ice-free in September – the month with the least ice – once in every hundred years. For global warming of 2°C, this would occur up to one year in every three.

“We will only be able to keep global warming to well below 2°C above pre-industrial levels if we effect unprecedented transitions in all aspects of society, including energy, land and ecosystems, urban and infrastructure as well as industry. The ambitious climate policies and emissions reductions required to deliver the Paris Agreement will also protect the ocean and cryosphere – and ultimately sustain all life on Earth,” said Roberts.

“This [report] has provided a new perspective on the scale of action that is required.”  

Sea Level Rise

As glaciers and ice sheets melt around the world, and the ocean expands as it warms, sea level will continue to rise twice as fast – and accelerate – past the 15cm (6 inches) already gained in the 20th century. Even if greenhouse gases are quickly reduced, sea level will continue to rise for centuries. It could become 30-60cm (1-2 feet) higher by 2100 in the best-case scenario, and 60-110cm (2-3.6 feet) if we do not cut emissions. 

At Ocean Conservancy, a few are calling it the “Climate Olympics” – faster, higher, stronger.

“All of the research is trending in one direction. The estimates [of sea level rise] are changing to come more quickly and more intensely than we’ve expected,” said Anna Zivian, Senior Research Fellow at the Ocean Conservancy and Co-chair of the Future Earth Ocean Knowledge-Action Network Development Team, who reviewed Chapter 4: Sea Level Rise as part of Ocean and Climate Platform’s Scientific Committee. 

“And we’re more certain of the effect. And we also know that a lot of the effects of sea level rise are going to be very serious for coastal communities as well as coastal habitats.”

680 million people live in low-lying coastal zones and another 65 million people live on small island developing states. They will be most directly impacted by the effects of sea level rise – which will also increase the frequency of extreme sea level events, which occur for example during high tides and intense storms. With any degree of additional warming, events that occurred once per century in the past will occur every year by mid-century in many regions. 

“The shoreline is going to be the front line of our sustainability struggle,” said Bruce Glavovic, coordinating lead author of Chapter 4: Sea Level Rise, Co-chair of the Executive Committee for Future Earth Coasts, and Professor at Massey University. 

Glavovic emphasizes the need to avoid new development commitments in coastal and low-lying areas with high and increasing risk, and Zivian points out the need to prepare for the changes that are already happening. 

For low-lying coastal zones and island states facing complete losses, Zivian says while the report doesn’t delve into specific solutions, it helps inform us of what our solutions can be.  

“We need to recognize that a number of the most effected regions and communities are ones that have been historically marginalized, underserved, and are vulnerable. And we need to act in ways that avoid exacerbating inequality and that avoid mal-adaptation,” said Zivian. 

Zivian points out that while the oceans and frozen areas on the planet seem far away to most people, many ocean solutions will be land-based, such as changing agricultural systems and energy systems. And she sees a need to frame these changes in a positive way – as opportunities, not challenges – despite their overwhelming nature. 

Polar Regions

Four million people live permanently in the Arctic, and are directly and disproportionately impacted by climate change. 

Yet 90 percent of the Earth’s ice is on the other side of the world in Antarctica and 70 percent of all available freshwater is locked up in the Antarctic ice sheet. The projections for future sea level rise are now higher than those from the previous assessments, because of the potential contribution of the Antarctic ice sheets to sea level rise. In addition to ice melt from warming atmospheric temperatures, warming water intrudes underneath the ice sheets floating on the ocean, which can quickly erode them from underneath, causing them to collapse into the ocean.

“Melt is expected to be greater than we had thought. One of the things that the Antarctic ice sheet is expected to do – we’re becoming more confident that it [melting] will increase, that it will contribute more to sea level rise than we had expected,” said Zivian. 

The Southern Ocean near Antarctica is also important for its role in absorbing heat and initiating global circulation patterns through the formation of ice at the edge of the continent, which drives the global conveyer belt of ocean currents. 

Jess Melbourne-Thomas, research scientist with CSIRO Oceans and Atmosphere and a member of the ICED (Integrating Climate and Ecosystem Dynamics) IMBeR Regional Programme, is a lead author on Chapter 3: Polar Regions and a contributing author to the summary for policy makers. ICED is one of four IMBeR Regional Programmes, and IMBeR (Integrated Marine Biosphere Research) is a global research project of Future Earth. In this report, Melbourne-Thomas focused on impacts of climate change on Southern Ocean ecosystems and also implications for human systems, but particularly fisheries.

“A consequence of ocean warming is that we’re seeing large scale redistribution of marine species generally in a pole-ward direction. And so that means that there is the potential for – and we’re already seeing – polar regions actually gain new species,” said Melbourne-Thomas. 

“From a fisheries perspective, the boundaries and jurisdictions of fisheries are changing because of species redistribution. We may see new fisheries emerging in regions like the Southern Ocean.”

Mountains and Glaciers

A total of 670 million people live in high mountain regions across the world, and are increasingly exposed to hazards and changes in water availability, according to the report. Glaciers, snow, ice and permafrost are declining and will continue to do so. This is projected to increase hazards for people, for example through landslides, avalanches, rockfalls and floods. Recreational activities, tourism, and cultural assets will also be negatively impacted. As mountain glaciers retreat, water availability and quality downstream also change, with implications for many sectors such as agriculture and hydropower.

Carolina Adler, Executive Director of the Mountain Research Initiative – a partner of Future Earth, is a lead author on Chapter 2: High Mountain Areas. Her focus for the report was on the observed and the projected changes in the mountain cryosphere: the glaciers, the permafrost, and the snow.

“What tends to happen is that we look at many studies that focus on just one mountain, or one valley, or one specific region. And there hasn’t been really a coordinated effort to look at an assessment that looks at this at a global scale,” said Adler.

“It was very insightful for us to learn how impacts manifest in different regions of the world: the Andes, the Himalayas, the European Alps, the Rockies in North America and so on… The common thread among them all is certainly the cryosphere decline – this is shrinking at an accelerating rate. And this is something that we see across all the mountain regions of the world,” said Adler. 

She echoes Glavovic, Zivian, and Melbourne-Thomas in advocating for rapid actions to reduce greenhouse gas emissions. The risks of scenarios with higher emissions are just too great, Adler said. “It’s certainly something that we would like to see avoided.” 

In Context 

This IPCC Special Report is a key scientific input for world leaders gathering in forthcoming climate and environment negotiations, such as the UN Framework Convention on Climate Change Conference (COP25) in Chile in December. It also precedes the United Nations Decade of Ocean Science for Sustainable Development, beginning in 2021. 

Zivian thinks that the Decade and COP25 are incredibly timely, as they can advantage of this and other recent IPCC special reports.  

“Without addressing climate change, it’s impossible to address ocean health,” Zivian said. 

The report also gives evidence of the benefits of combining scientific, both local and indigenous knowledge, to develop suitable options to manage climate change risks and enhance resilience. 

“And that means we need to draw more people to the table than we’ve had before… we need to access indigenous knowledge, local knowledge, we need to have communities at the table who experience these impacts and can enable a new discussion,” said Roberts.  

This Special Report will also inform upcoming global events such as Sustainability Research and Innovation 2020 (SRI2020), a first-of-its-kind event, established by Future Earth and the Belmont Forum, which will gather together academia, business, NGOs, and governments in one common goal: to meet global sustainability challenges.