Monday’s IPCC report is a really big deal for climate change. So what is it? And why should we trust it?

Chinatopix via AP

David Karoly, CSIROOn Monday, an extremely important report on the physical science of climate change will be released to the world. Produced by the Intergovernmental Panel on Climate Change (IPCC), the report will give world leaders the most up-to-date information about climate change to inform their policies.

It is an enormous undertaking, and has been a long time coming.

This report is the culmination of a marathon five-year assessment, writing, review and approval process from 234 leading scientists hailing from more than 60 countries. These scientists have worked together to rigorously evaluate the world’s climate change research papers — more than 14,000 of them.

I’ve been involved with the IPCC reports in multiple roles since 1997. For this current report, I was a review editor for one chapter.

This IPCC assessment report is the sixth overall, and the first since 2013. A lot has changed since then, from major governments setting ambitious climate targets, to devastating floods, fires and heatwaves across the world.

So what is the IPCC, and why does this report matter so much? And given the report is commissioned and approved by national governments, should we trust it?

What is the IPCC?

The Intergovernmental Panel on Climate Change was first established in 1988 by the United Nations Environment Programme and the World Meteorological Organization. Their aim was to provide policymakers with regular and comprehensive scientific assessments on climate change, at a time when climate change was becoming a more mainstream concern around the world.

These reports assess the scientific basis of climate change, its impacts and future risks, and options for adaptation and mitigation. They’re required to be policy-relevant yet policy-neutral. They contain findings, and state the confidence with which the finding is made, but do not recommend action.

This report is the sixth since the IPCC was established in 1988.
Shutterstock

The first assessment was completed in 1990, and found:

emissions resulting from human activities are substantially increasing the concentrations of […] carbon dioxide [and other greenhouse gases]. These increases will enhance the greenhouse effect, resulting on average in an additional warming of the Earth’s surface.

Since then, new assessment cycles have been completed every five to seven years.

The overall assessment — the Sixth Assessment Report — is divided into three main parts. Monday’s report is the first part – on the physical science basis for climate change – and was delayed by almost a year due to COVID restrictions.

The next two parts will be released in 2022. One will cover the impacts, adaptation and vulnerability of, for example, people, ecosystems, agriculture, cities, and more. The other will cover the economics and mitigation of climate change.

The Sixth Assessment Report will culminate in a synthesis report, combining the first three parts, in September 2022.

What will we learn?

The report will provide the most updated and comprehensive understanding of the climate system and climate change, both now and into the future. For that reason, it’s relevant to everyone: individuals, communities, businesses and all levels of government.

---

Read more:
Climate explained: how the IPCC reaches scientific consensus on climate change

---

It will tell us how fast carbon dioxide emissions have been rising, and where they’re coming from. It’ll also tell us how global temperatures and rainfall patterns have changed, and how they are expected to change this century, with associated confidence levels.

Compared to the previous report in 2013, this report puts greater emphasis on regional climate change, on changes in extreme events, and how these events are linked to human-caused climate change.

This greater emphasis on extreme events at regional scales makes it even more important to policy makers and the public.

In recent months the world has watched in horror as heatwaves, bushfires and floods toppled homes and buildings, killing hundreds across China, Europe and North America. The report will help put disasters like these in the context of climate change, noting that similar events are expected to be more frequent and severe in a warming world.

The report also examines the effects of different levels of global warming, such as 1.5℃ and 2℃. It also looks at when such warming is likely to be reached.

---

Read more:
5 things to watch for in the latest IPCC report on climate science

---

Why should I trust it?

The scope of each IPCC report is prepared by scientists and approved by representatives of all governments. The 234 scientists who wrote the report are selected based on their expertise, and represent as many countries as possible.

The reports go through multiple stages of drafting and review. The first draft of the current report had more than 23,000 review comments from experts. Each comment received an individual response.

The second draft had more than 50,000 review comments from experts and governments, and these guided the preparation of the final draft.

You may be thinking that the IPCC reports should not be trusted because they involve government inputs and approval. However, this is probably one of their strengths. Involving government representatives ensures the reports are relevant to the policy interests of all governments.

Indeed, the multi-stage review and revision process used for the IPCC reports has been used as a model for international assessments of other scientific topics.

Can I read it?

The report will be released and free to read at 6pm Australian Eastern Standard time (10am Paris time) on Monday. But each chapter in the final report will be more than 100 pages long in a small font, so few people will read it all.

The most accessible part of the report is its Summary for Policymakers, aimed at a general readership and drafted by the expert authors.

The approval meeting for this report has been taking place over the last two weeks in Paris, as a video conference meeting of government representatives. The meeting approves each chapter, but most time is spent considering and approving the Summary for Policymakers.

---

Read more:
Top climate scientist: I put myself through hell as an IPCC convening lead author, but it was worth it

---

Every line in this summary is considered separately, comments from government representatives are considered, and changes must be approved by consensus of all governments. Sometimes reaching consensus can take a long time.

It’s clear the IPCC brings the best of global science together. It’s vital that governments keep the findings of this report front of mind in their decision-making, if the world is to avoid the worst-case climate scenarios.

David Karoly, Chief Research Scientist, CSIRO

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Advertisement

Giant bird-eating centipedes exist — and they’re surprisingly important for their ecosystem

Luke Halpin, Monash University; Rohan Clarke, Monash University, and Rowan Mott, Monash UniversityGiant bird-eating centipedes may sound like something out of a science-fiction film — but they’re not. On tiny Phillip Island, part of the South Pacific’s Norfolk Island group, the Phillip Island centipede (Cormocephalus coynei) population can kill and eat up to 3,700 seabird chicks each year.

And this is entirely natural. This unique creature endemic to Phillip Island has a diet consisting of an unusually large proportion of vertebrate animals including seabird chicks.

Phillip Island in the Norfolk Island group, with a valley of iconic Norfolk Island Pine trees.
Luke Halpin

As large marine predators, seabirds usually sit at the top of the food chain. But our new study, published in The American Naturalist, demonstrates this isn’t always the case.

We show how large, predatory arthropods can play an important role in the food webs of island ecosystems. And the Phillip Island centipede achieves this through its highly varied diet.

---

Read more:
Ancient marvels: the first shell-crushing predators ground up their prey between their legs

---

A well-armed predator stirs in the night

This centipede can grow to almost one foot (or 30.5cm) in length. It is armed with a potent venom encased in two pincer-like appendages called “forcipules”, which it uses to immobilise its prey. Its body is protected by shield-like armoured plates that line each of the many segments that make up its length.

On warm and humid nights, these strictly nocturnal arthropods hunt through thick leaf litter, navigating a labyrinth of seabird burrows peppered across the forest floor. A centipede on the prowl will use its two ultra-sensitive antennae to navigate as it seeks prey.

The centipede hunts an unexpectedly varied range of quarry, from crickets to seabird chicks, geckos and skinks. It even hunts fish — dropped by seabirds called black noddies (Anous minuta) that make their nests in the trees above.

A frightful discovery

Soon after we began our research on the ecology of Phillip Island’s burrowing seabirds, we discovered chicks of black-winged petrels (Pterodroma nigripennis) were falling prey to the Phillip Island centipede.

We knew this needed further investigation, so we set out to unravel the mystery of this large arthropod’s dietary habits.

Black-winged petrel chick just prior to being weighed on Phillip Island.
Trudy Chatwin

To find out what these centipedes were eating, we studied their feeding activities at night and recorded the prey species they were targeting. We also monitored petrel chicks in their burrow nests every few days, for months at a time.

We eventually began to see consistent injury patterns among chicks that were killed. We even witnessed one centipede attacking and eating a chick.

From the rates of predation we observed, we calculated that the Phillip Island centipede population can kill and eat between 2,109 and 3,724 petrel chicks each year. The black-winged petrels — of which there are up to 19,000 breeding pairs on the island — appear to be resilient to this level of predation.

Envenomation of a black-winged petrel nestling by a Phillip Island centipede. (Video by Daniel Terrington)

And the predation of black-winged petrels by Phillip Island centipedes is an entirely natural predator-prey relationship. By preying on vertebrates, the centipedes trap nutrients brought from the ocean by seabirds and distribute them around the island.

In some sense, they’ve taken the place (or ecological niche) of predatory mammals, which are absent from the island.

Luke Halpin monitoring black-winged petrel chicks on Phillip Island.
Trudy Chatwin

Restoration and recovery

Up until just a few decades ago the Phillip Island Centipede was very rare. In fact, it was only formally described as a species in 1984.

After an intensive search in 1980, only a few small individuals were found. The species’s rarity back then was most likely due to severely degraded habitats caused by pigs, goats and rabbits introduced by humans to the island.

The removal of these invasive pests enabled black-winged petrels to colonise. Their population has since exploded and they’re now the most abundant of the 13 seabird species that breed on Phillip Island.

They provide a high-quality food source for the Phillip Island centipede and have therefore likely helped centipede population to recover.

Black-winged petrels on Phillip Island are active both during the day and at night. (Video by Luke Halpin)

Ancient bone deposits in the soil suggest that prior to the black-winged petrel’s arrival, Phillip Island was home to large numbers of other small burrow-nesting seabird species. It’s likely the Phillip Island centipede preyed on these seabirds too.

Now, thanks to the conservation efforts of Norfolk Island National Park, the island’s forest is regenerating alongside endemic species like the centipede, as well as the critically endangered Phillip Island hibiscus (Hibiscus insularis).

The endemic Phillip Island hibiscus.
Luke Halpin

As a driver of nutrient transfer, the persistence of the Phillip Island centipede (and its healthy appetite) might just be key to the island’s ecosystem recovery. But we’ll need to do more research to fully understand the intricate links in this bustling food web.

---

Read more:
These underwater photos show Norfolk Island reef life still thrives, from vibrant blue flatworms to soft pink corals

---

Luke Halpin, Ecologist, Monash University; Rohan Clarke, Director, Monash Drone Discovery Platform, and Senior Lecturer in Ecology, Monash University, and Rowan Mott, Biologist, Monash University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Complicated, costly and downright frustrating: Aussies keen to cut emissions with clean energy at home get little support

Hugo Temby, Australian National University and Hedda Ransan-Cooper, Australian National UniversityEven after A$4,000 in repairs, Heather’s $18,000 rooftop solar and battery system is still not working.

Heather worked as a nurse until a workplace accident caused her to leave the workforce. She put most of her compensation towards making a switch to clean energy, hoping to bring down her energy costs and increase her comfort.

But a solar company sold her a system that wasn’t suited to her needs. They also didn’t clearly explain how the system worked or how to maintain it.

Heather’s battery failed after roughly two years. Her system’s complexity, and the limited handover provided by the company, meant she didn’t notice its failure during the short warranty period. Reflecting on the technical written information provided to her, Heather told us it was “way over my head”.

As a result, she is fully responsible for the cost of repairs, which she cannot afford. And she has since been told the battery is irreparable.

Heather’s story is one of many featured in our new report published today. It shows household clean energy technologies — such as rooftop solar, household batteries and electric vehicles — can be unnecessarily complicated, time consuming and costly.

Switching to clean energy at home

The aim of our report was to better understand stories like Heather’s to inform a Victorian Energy and Water Ombudsman review of the various new energy technology regulatory frameworks in Australia. These frameworks have not kept up with the pace of technological change.

We held in-depth interviews in 2020 and 2021 with 68 householders, businesses and industry experts based mainly in Victoria and South Australia. We asked why people were purchasing new energy technology, if it was meeting their expectations, and the issues people were encountering.

Switching to clean energy technologies from old, emissions-intensive ones shouldn’t be this hard.
Shutterstock

Nearly all householders we spoke with were motivated to some degree by environmental concerns, particularly the desire to reduce their emissions, and many expected some financial returns. Community mindedness, enthusiasm for technology and comfort were other common motivators.

And many wanted greater independence from untrusted energy companies. Distrust of the sector has multiple facets, but it often boils down to a sense the sector doesn’t have the long-term interests of the public in mind.

Going it alone

New energy technologies can be highly complex. It’s not always clear what differentiates one solar panel product from another. Some services, such as virtual power plants or battery aggregation, require a basic understanding of how the broader energy system works, which even energy insiders can struggle to understand.

Some householders told us they found it difficult to source reliable information about different electric vehicle products, which they felt weren’t being sufficiently well covered in mainstream car magazines.

---

Read more:
‘Smart home’ gadgets promise to cut power bills but many lie idle – or can even boost energy use

---

Meanwhile, many householders felt alone and unsupported in dealing with their new technology. Heather, for example, has gone through four different electricians.

Most told us they were investing significant time, effort and funds into researching, choosing, configuring and operating their technologies, with different technologies often interacting and various energy tariffs on offer.

Increasingly, people are being seen as idealised “prosumers” in a “two-sided market”. In other words, rather than asking people how they might like to engage with the energy system, householders are given narrow options revolving around solely financial mechanisms.

Australians need support to cut transport emissions with electric vehicles.
Shutterstock

Most Australians don’t have the time and resources to do this work. Without a whole-of-sector strategy to ensure all Australians benefit from new energy technologies, we risk leaving people behind. This includes renters, apartment dwellers, people who can’t afford high up-front costs, or people who simply don’t have the time to do all the extra “digital housework” to maintain these technologies.

Alternative models, such as social enterprises or community energy, could make technology more accessible to renters and low income households. One example of this is solar gardens, where people can buy a share in a solar array located nearby, which in turn provides them with a discount on their bill.

But arguably, such options wouldn’t be required if our emerging energy system had resolved the energy trilemma in the first place.

Why this is so concerning

We know householders are a key part of the solution for climate mitigation, together with businesses and government.

There are many ways householders can decarbonise their electricity and transport. While not all involve buying new energy products, we consistently heard frustration about the lack of a coherent framework for different ways they could contribute.

---

Read more:
‘Die of cold or die of stress?’: Social housing is frequently colder than global health guidelines

---

According to the federal government, it will be “technology, not taxes” that will get us to our Paris emissions reduction commitments.

But this assumes new technology uptake will be straightforward and downplays potential risks. It also implies new technology is always preferable to alternatives like reducing consumption.

A narrow focus on technology also ignores the rebound effect. Research has shown that without deeper engagement with Australians about the energy system, it’s possible lower electricity costs from new energy technologies could actually increase energy use and emissions.

The federal government’s ‘technology not taxes’ approach to energy policy assumes new tech uptake will be straightforward.
Shutterstock

Where do we go from here?

Our new research shows we need better support for the nearly 2.8 million (and growing) Australian households and businesses that have already purchased new, clean energy technologies.

To make this happen, we need coordinated, climate wise policy across all levels of government with an engaged, evidence-based and equitable energy policy. This would help rebuild trust in Australia’s energy system.

If our national climate policy is to rely on new energy technology, it will be critical to ensure the technology – and its implementation – is better aligned with people’s needs and aspirations.

---

Read more:
‘I can’t save money for potential emergencies’: COVID lockdowns drove older Australians into energy poverty

---

Hugo Temby, Doctoral Researcher, Battery Storage and Grid Integration Program, Australian National University and Hedda Ransan-Cooper, Research Fellow, College of Engineering and Computer Science, Australian National University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Super Roots

Oil Rigs Near Reefs?