Tag Archives: climate crisis

If the atmosphere is chaotic, how can we trust climate models?

Before they can understand how our planet’s climate is changing, scientists first need to understand the basic principles of this complicated system — the gears that keep the Earth’s climate turning. You can make simple models with simple interactions, and this is what happened in the first part of the 20th century. But starting from the 1950s and 1960s, researchers started increasingly incorporating more complex components into their models, using the ever-increasing computing power.

But the more researchers looked at climate (and the atmosphere, in particular), the more they understood that not everything is neat and ordered. Many things are predictable — if you know the state of the system today, you can calculate what it will be like tomorrow with perfect precision. But some components are seemingly chaotic.

Chaos theory studies these well-determined systems and attempts to describe their inner workings and patterns. Chaos theory states that behind the apparent randomness of such systems, there are interconnected mechanisms and self-organization that can be studied. So-called chaotic systems are very sensitive to their initial conditions. In mathematics (and especially in dynamic systems), the initial conditions are the “seed” values that describe a system. Even very small variations in the conditions today can have major consequences in the future.

It’s a lot to get your head around, but if you want to truly study the planet’s climate, this is what you have to get into.

The Butterfly Effect

Edward Lorenz and Ellen Fetter are two of the pioneers of chaos theory. These “heroes of chaos” used a big noisy computer called LGP-30 to develop what we know as chaos theory today.

Lorenz used the computer to run a weather simulation. After a while, he wanted to run the results again, but he just wanted half of the results, so he started the calculations using the results from the previous run as an initial condition. The computer was running everything with six digits, but the results printed were rounded to 3 digits. When the calculations were complete, the result was completely different from the previous one.  

That incident resulted in huge changes for the fields of meteorology, social sciences and even pandemic strategies. A famous phrase often used to describe this type of situation is “the butterfly effect”. You may be familiar with the idea behind it: “The flap of a butterfly’s wings in Brazil can set off a Tornado in Texas”. This summarizes the whole idea behind the small change in the initial conditions, and how small shifts in seemingly chaotic systems can lead to big changes. 

Simulation of Lorenz attractor of a chaotic system. Wikimedia Commons.

To get the idea, Lorenz went on to construct a diagram that depicts this chaos. It is called the Lorenz Attractor, and basically, it displays the trajectory of a particle described by a simple set of equations. The particle starts from a point and spirals around a critical point — a chaotic system is not cyclical so it never returns to the original point. After a while, it exceeds some distance and starts spiraling around another critical point, forming the shape of a butterfly. 

Why is it chaotic?

If the atmosphere is chaotic, how can we make predictions about it? First, let’s clarify two things. Predicting the weather is totally different from predicting the climate. Climate is a long period of atmospheric events, on the scale of decades, centuries, or even more. The weather is what we experience within hours, days, or weeks. 

Weather forecasting is based on forecast models which focus on predicting conditions for a few days. To make a forecast for tomorrow, the models need today’s observations as the initial condition. The observations aren’t perfect due to small deviations from reality but have improved substantially due to increases in computation power and satellites.

However, fluctuations contribute to making things harder to predict because of chaos. There is a limit to when the predictions are accurate — typically, no more than a few days. Anything longer than that makes the predictions not trustworthy. 

Thankfully, our knowledge about the atmosphere and technological advances made predictions better compared to 30 years ago. Unfortunately, there are still uncertainties due to the chaotic atmospheric behavior. This is illustrated in the image below, the model’s efficiency is compared between the day’s ranges. The 3-day forecast is always more accurate, compared to predictions from 5 to 10 days. 

The evolution of weather predictability. Credits: Shapiro et al. (AMS).

This image also shows an interesting societal issue. The Northern Hemisphere has always been better at predicting the weather than the South.

This happens because this region contains a larger number of richer countries that developed advanced science and technology earlier than the Global South, and have more monitoring stations in operation. Consequently, they used to have many more resources for observing the weather than poorer countries. Without these observations, you don’t have initial conditions to use for comparison and modeling. This started to change around the late ’90s and early 2000s when space agencies launched weather satellites that observe a larger area of the planet.

Predicting the climate

Predicting the climate is a different challenge, and in some ways, is surprisingly easier than predicting the weather. A longer period of time means more statistical predictability added to the problem. Take a game of chance, for instance. If you throw dice once and try to guess what you’ll get, the odds are stacked against you. But throw a dice a million times, and you have a pretty good idea what you’ll get. Similarly, when it comes to climate, a bunch of events are connected on average to long-term conditions and taken together, may be easier to predict.

In terms of models, there are many different aspects of weather and climate models. Weather models can predict where and when an atmospheric event happens. Climate models don’t focus on where exactly something will happen, but they care how many events happen on average in a specific period.

When it comes to climate, the Lorenz Attractor is the average of the underlying system conditions — the wings of the butterfly as a whole. Scientists use an ensemble of smaller models to ‘fill the butterfly’ with possibilities that on average represent a possible outcome, and figure out how the system as a whole is likely to evolve. That’s why climate models predictions and projections like those from the IPCC are extremely reliable, even when dealing with a complex, seemingly chaotic system.

Comparing models

Today, climate scientists have the computer power to average a bunch of models trying to predict the same climate pattern, further finessing the results. They can also carry out simulations with the same model, changing the initial conditions slightly and averaging the results. This provides a good indicator of what could happen for each outcome. Even further than that, there is a comparative workforce between the scientific community to show that independent models from independent science groups are agreeing about the effects of the climate crisis.

Organized in 1995, the Coupled Model Intercomparison Project (CMIP) is a way of analysing different models. This workforce makes sure scientists are comparing the same scenario but with different details in the calculations. With many results pointing to a similar outcome, the simulations are even more reliable.

Changes in global surface temperature over the past 170 years (black line) relative to 1850–1900 and annually-averaged, compared to CMIP6 climate model simulations of the temperature response to both human and natural drivers (red), and to only natural drivers (solar and volcanic activity, green). Solid coloured lines show the multi-model average, and coloured shades show the range (“very likely”) of simulations. Source: IPCC AR6 WGI>

Ultimately, predicting the climate is not like we are going to predict if it will be rainy on January 27 2122. Climate predictions focus on the average conditions that a particular season of an oscillatory event will be like. Despite the chaotic nature of the atmosphere, thanks to climate’s time length and statistical predictability, long-term climate predictions can be reliably made.

Healthier, more nutritious diets have a lower environmental impact — at least in the UK

More nutritious and healthy diet options can also help the climate, says a new analysis from the University of Leeds.

Image via Pixabay.

Our combined dietary habits can be a significant source of greenhouse gas emissions. Worldwide, food production accounts for roughly one-third of all emissions. This isn’t very surprising, since everybody needs to eat; but there are little tweaks we can apply to our lives which, added up, can lead to significant benefits for the climate.

New research at the University of Leeds reports that more nutritious, less processed, and less energy-dense diets can be much more sustainable from an environmental point of view than more common alternatives. While “less energy-dense” might sound like a bad thing, calorie content doesn’t translate into nutrient content. In other words, many energy-rich foods may actually just leave us fatter and malnourished.

Clean dining

“We all want to do our bit to help save the planet. Working out how to modify our diets is one way we can do that,” the authors explain. “There are broad-brush concepts like reducing our meat intake, particularly red meat, but our work also shows that big gains can be made from small changes, like cutting out sweets, or potentially just by switching brands.”

Similar analyses of the impacts of dietary options on the environment have been performed in the past. While their findings align well with the conclusions of the study we’re discussing today, they focused on broad categories of food instead of specific items. The team wanted to improve the accuracy of our data on this topic.

For the study, they pooled together published research on greenhouse gas emissions associated with food production to estimate the environmental impact of 3,233 specific food items. These items were selected from the UK Composition Of Foods Integrated Dataset (COFID). This dataset contains nutritional data regarding every item on the list and is commonly used to gauge the nutritional qualities of individuals’ diets.

The team used this data to evaluate the diets of 212 participants, who were asked to report what foods they ate during three 24-hour periods. In the end, this provided a snapshot of each participant’s usual nutritional intake and the greenhouse emissions generated during the production phase of all the items they consumed.

What the results show, in broad strokes, is the environmental burden of different types of diets, broken down by their constituent elements.

According to the findings, non-vegetarian diets had an overall 59% higher level of greenhouse gas emissions compared to vegetarian diets. This finding isn’t particularly surprising; industrial livestock farming is a big consumer of resources such as food and water and produces quite a sizeable amount of emissions from the animals themselves, the production of fodder, and through the processing and storage of meat and other goods.

Overall men’s diets tended to be associated with higher emissions — 41% more on average than women’s diets — mainly due to higher meat consumption.

People who exceeded the recommended sodium (salt), saturated fat, and carbohydrate intake as set out by World Health Organization guidelines generated more emissions through their diets than those who did not.

Based on these findings, the authors offer their support for policies aimed at encouraging sustainable diets, especially those that are heavily plant-based. One other measure they are in support of is policy that promotes the replacement of coffee, tea, and alcohol with more sustainable alternatives.

The current study offers a much higher-resolution view of the environmental impact of different food items, but it is not as in-depth as it could be. In the future, the authors hope to be able to expand their research to include elements such as brand or country of origin to help customers better understand what choices they’re making. They also plan to include broader measures of environmental impact in their analyses, not just greenhouse gas emissions.

For now, the findings are based only on data from the UK, so they may not translate perfectly to other areas of the globe.

The paper “Variations in greenhouse gas emissions of individual diets: Associations between the greenhouse gas emissions and nutrient intake in the United Kingdom” has been published in the journal PLOS One.

G20 leaders promise big climate efforts but make few tangible commitments

There’s a distinct irony to Boris Johnson calling out world leaders for their hollow promises on climate change.

The UK Prime Minister, who said these promises are “starting to sound hollow” and that the commitments are “drops in a rapidly warming ocean”, is familiar to hollow promises himself. Johnson has often been criticized for his failure to deliver on a number of topics, including climate. The UK recently announced its plan to transition to zero emissions, but many have pointed out that the plan is also short on specifics and rings hollow at different places.

So when, after intense all-night negotiations, world leaders finally agreed to a joint declaration on climate change, we can probably be excused for not getting our hopes up.

Sure, on paper, things look good. Not only did the leaders of G20 (which accounts for 80% of the world’s emissions and includes the European Union plus the world’s 19 richest countries) reiterate their support of the Paris Agreement to limit climate warming within 2°C, but they even made a push for 1.5°C.

“We remain committed to the Paris Agreement goal to hold the global average temperature increase well below 2°C and to pursue efforts to limit it to 1.5°C above pre-industrial levels, also as a means to enable the achievement of the 2030 Agenda,” the leaders said in a statement. “We recognize that the impacts of climate change at 1.5°C are much lower than at 2°C.”

But ultimately, the agreement made few concrete commitments. US President Joe Biden said there were a “series of very productive meetings”, but he rightly pointed out that China and Russia (among the world’s biggest polluters) “basically didn’t show up” on matters of the climate. In fact, China and Russia, along with India and Australia, made a push against a firm statement about ending the use of coal. European diplomats were pushing on a firm target to end the use of coal, but supporters of fossil fuel could not be budged.

The leaders agreed to end international public financing of new coal power by the end of this year, but domestic financing of coal plants was not addressed — let alone ending the use of coal altogether. This political stalemate does not bode well for COP26 — the global climate summit that starts today.

Five years ago, at the 21th COP in Paris, we got the Paris Agreement — the landmark international climate pact in which all countries agreed to limit their emissions to keep temperature rise to within 2 degrees Celsius — and now it’s time for countries to update their national plans to reduce emissions — hopefully with more ambitious plans.

But this doesn’t seem to be the case. Even if current committments are respected (which is already a big ‘if’) that only puts us on a trajectory for a warming of 3 degrees Celsius.

So if we are to avoid catastrophic climate change, we need more tangible action and we need it now. There seems to be an impending feeling of “now or never” in the air, with Boris Johnson telling G20 leaders that “If Glasgow fails, then the whole thing fails.” Unfortunately, many felt that the G20 didn’t deliver. Oscar Soria, of the activist network Avaaz, told the agency there was “little sense of urgency” coming from the group, adding: “There is no more time for vague wish lists, we need concrete commitments and action.”

Even António Guterres, Secretary-General of the United Nations expressed his disappointment with the result, saying his hopes are “unfulfilled” but at least “not buried.”

Still, not all is lost yet. France’s President Emmanuel Macron told newspaper Journal du Dimanche that “nothing is ever written before a COP”, while a US official told reporters that G20 was about “helping build momentum” before the leaders head to Glasgow for COP. With the conference kicking off today, the message of G20 leaders is expected to set the tone for negotiations and lend a push for the uphill battle of fighting climate change.

We’ve seen in the pandemic that the world can take decisive action quickly with the right drive, and climate change is a challenge equal in scale (or even greater) than the pandemic. Hopefully, world leaders will manage to recreate that same drive and put the world on a path that avoids some of the worst effects of climate change.

The scientific consensus is that if global temperatures rise by 2 degrees Celsius, the likelihood of climate catastrophes increases substantially. This translates into increased global hunger, water crises, disease, and conflict. Even 1.5 degrees would be problematic, but it is much more manageable than 2 degrees. Meanwhile, the 3 degrees warming we’re currently headed for would be catastrophic, bringing devastating loss of life and economic decline across all of the planet. It’s pretty much our last chance to take action that avoids all these negative effects. If we don’t act, the window of opportunity may soon be closed.

A deep look at carbon capture and storage (CCS) and its role in the climate crisis

Carbon Capture and Storage (CCS) is the process of capturing carbon dioxide (CO2), a greenhouse gas, and depositing it somewhere it will not reach the atmosphere again — typically in a suitable geological formation. The goal is to reduce the amount of greenhouse gases in the atmosphere and limit (or even reverse) man-made climate heating.

Does it work?

It’s not science fiction. The technology already exists and several projects are already underway. The carbon dioxide is typically extracted from a single point source (like a cement factory or a fossil fuel facility), and injected into a porous structure where the CO2 can be absorbed without leaking back into the atmosphere. Carbon dioxide can also be absorbed from the air, although the efficacy of this process is much lower.

Carbon capture and storage can reduce the emissions of a plant by up to 90% and when coupled with other technologies, CCS can even lead to negative emissions.

The technology is regarded by many researchers as a key tool in our fight against global warming and greenhouse gas emissions as it is not only a way to reduce our emissions, but maybe even to grab some of the greenhouse gases already present in the atmosphere and store them. However, CCS comes in many different forms and, at this moment, there are only a handful of operating CCS projects in the world.

Simply put, it works — the physics of the process is valid. But whether or not CCS will really be used on a wide scale and help us keep climate change in check is a very different question.


The planet is heating up. Over the past century, the planet’s average surface temperature has risen by about 2 degrees Fahrenheit (a bit over 1 degree Celsius) — a change driven largely by increased carbon dioxide and other man-made emissions into the atmosphere.

We won’t get into the details of how we know climate change is happening and that it’s caused by mankind. All the available figures and scientific evidence point in this direction. Greenhouse gas emissions have increased steadily since 1890, and as a result, temperatures are rising. The problem is very real and burying our head in the sand won’t help one bit.

If we want to truly manage this crisis, we need to reduce our emissions, achieve net zero emissions, and, ultimately, find ways to revert previous emissions. The good news is that CCS can help with both.

Right now, society most focused on producing renewable energy to replace polluting and carbon-intensive fossil fuels. In truth, it’s not just just the environmental aspect of it, renewable energy is already cheaper in many parts of the world (but that’s a different story). Important as this may be, it’s not enough on its own.

A substantial part of our emissions comes from other industrial activities (like cement factories, for instance) which are extremely hard to decarbonize, and it’s not like all fossil fuel power plants will disappear overnight — we need to reduce emissions from them in the meantime. This is where CCS can come in and make a difference.

However, we can’t just capture carbon dioxide, put it in a box and wash our hands, it just doesn’t work that way. You can’t build a carbon storage factory. Luckily enough though, nature has done that herself.

Geology to the rescue

Some subsurface geological features are excellently suited as carbon storage sites. Some brine-filled pores in sandstone formations, or other similar structures sealed by a natural and impermeable caprock such as a shale or clay. Essentially, you need a porous rock to inject the carbon in, and impermeable rocks to act as a seal around it.

In some contexts, carbon storage has been used for several decades (most notably for enhanced oil recovery), but as a tool to tackle global heating, it’s a relatively new concept. For many current CCS projects, the technology used to lock CO₂ deep underground is the same technology used to enhance oil reservoirs. In one oil field (called Sleipnir), some 23 million tons of CO₂ have been injected underground. In the case of Sleipnir, the positive effect of injecting CO₂ is counterbalanced by the extraction (and subsequent burning) of oil. But what if we could just have the positive effect and not do the oil part? That’s pretty much how the idea of carbon storage emerged.

It’s been actively researched in the US since 1997, but the technology first took off in Norway in the 1980s. Although the basic principle is still the same, CCS as a field of science has grown and developed massively since. CCS publications and studies have increased exponentially in the past 20 years, with international collaboration spurring multiple projects. Still, as of 2019, there are only 17 operating CCS projects in the world, capturing 31.5Mt of CO₂ per year, of which just 3.7 is stored geologically. Compare that to the 5.1 billion metric tons of energy-related carbon dioxide the US emitted in 2019 alone — it takes the US just a couple of days to emit more CO₂than is stored year-round in the entire world.

But this doesn’t mean that CCS can’t grow. The latest IPCC Assessment Report on Mitigation mentioned CCS 35 times in the summary for policymakers. The International Energy Agency has repeatedly said CCS is a key technology for mitigating climate change. More and more, researchers are looking at CCS as one of the key ways to address some parts of our greenhouse gas emissions.

At the very least, the geological potential is there. The US National Energy Technology Laboratory (NETL) reported that North America has enough storage capacity for more than 900 years worth of carbon dioxide at current production rates. Even though there is some uncertainty regarding potential long-term leaking, there’s still more than enough room for the world to dump its carbon underground.

Location, location, location (and technology)

Carbon capture and storage is most effective when it’s applied at point sources such as a single factory or a single storage site — it’s far less effective when dealing with multiple, smaller sources. This is what makes it an excellent technology for heavy-emission industries.

Exasmple of how CCS can work at a biomass plant. Image credits: Wiki Commons.

There are three main types of carbon capture and storage for industrial facilities:

  • post-combustion capture is the most widely used form of carbon capture and storage. It essentially refers to capturing CO₂ from a flue gas generated after combusting a carbon-based fuel, such as coal or natural gas. A number of different techniques are used ,and post-combustion capture is especially interesting for researchers because existing fossil fuel power plants can be retrofitted to include CCS technology in this configuration.
  • pre-combustion capture is widely applied in fertilizers, gaseous fuel (H2, CH4), and power production. The advantage is you also obtain hydrogen which can be used as a fuel. However, retrofitting plants to accommodate pre-combustion capture is challenging and this is mostly an option for new plants.
  • oxy-fuel combustion, where the fuel is burned in oxygen instead of air. This results in a flue gas that is mainly CO₂ and water.

There are multiple technologies for separating CO2, becoming more and more efficient every year. But after it’s separated, the CO2 must be transported. This is most easily done via pipes (and has been done before). For instance, there were approximately 5,800 km of CO2 pipelines in the United States in 2008, and a 160 km pipeline in Norway used for enhanced oil recovery.

After it’s separated and transported, it is injected into a suitable geological reservoir.

Negative emissions — taking carbon from the atmosphere

So far, we’ve mostly focused on using CCS for factories, as a way to reduce emissions. But CCS can also be used as a way to revert emissions — or, as researchers put it, to produce negative emissions.

Cement amounts for about 8% of the world’s greenhouse gas emissions. Image credits: Kåre Helge Karstensen, SINTEF.

The underlying principle is straightforward: you extract carbon from sources in the Earth’s biological cycle and inject them on the ground. This way, you’re not just reducing the carbon you’re outputting, you’re essentially eliminating some of the already existing carbon. So you would take something like wood chips or biological waste such as manure and inject the carbon from it to a geological storage site.

But it can get even more interesting than that. In a recent study, researchers discovered a way to pull carbon dioxide from the atmosphere and turn it back into coal. This approach is actively being researched by fossil fuel companies, who are looking for a way to maximize returns. However, in order for this to truly have a net positive effect, the subsequent burning of the resulting coal would also have to be captured.

Perhaps the most exciting development comes from Iceland, where researchers found a way to extract CO2 and mineralize it into rocks. They’ve essentially created ‘negative emissions plant’ — a plant that turns ambient CO2 into stone switches.

Iceland’s large basaltic fields could be a boon for CCS. Image via Unsplash.

The key to rapid mineralization of carbon is basalt – a volcanic rock which Iceland has an abundance of. Iceland is actually mostly made up of basalt (90%), and within basalt, CO2 can quickly mineralize (morph into carbonate rocks). “The potential of scaling-up our technology in combination with CO2 storage, is enormous,” said Christoph Gebald, the founder and CEO of Climeworks, the company behind the technology.

But for all these exciting developments, there’s one part we’ve purposely left out until now: money.

Without a carbon tax, CCS just won’t work

What about the money? As we’ve seen in the case of renewable energy, green technologies can only truly succeed when they have at least some economic advantage. Separating CO₂ from other chemicals is costly and also requires energy. But unlike renewable energy, in the case of CCS, there’s no real economic advantage — all you have is a method of reducing CO₂ emissions, that’s it.

At the moment, even as CCS is making great strides in terms of technology and research, the funding for said technologies is starting to shrink. This is a problem not just for carbon storage, but for our ability to meet current climate commitments and avoid catastrophic environmental and economic damage.

Nowadays, CCS projects rely on government incentives and standards — even though economists generally agree that these programs are less effective and more costly than a carbon price. Carbon pricing is notoriously unpopular and hotly debated, but increasingly, leading economists are calling for some sort of a climate tax. Without such a tax (or some pricing mechanism), CCS remains a niche technology and is unlikely to scale massively into the future.

“I prefer to have an economy-wide carbon price to create markets for low-carbon technology. Then markets, not advocates, will make decisions about the technology mix. I believe deployment of CCS would be significant under such a policy,” writes Howard J. Herzog Senior Research Engineer, Massachusetts Institute of Technology.

Simply put, new policies are dearly needed to incentivize commercial CCS. No matter how you look at things reaching net-zero emissions (and maybe, someday even negative emissions) seems much harder without CCS — but without financial incentives CCS cannot flourish, even when the technology matures. A University of Warwick report concludes:

“CCS has considerable potential to reduce CO2 emissions not only by a significant amount but also at a social cost that most economists would not consider prohibitive, particularly in comparison to the social costs predicted for a business-as-usual scenario with unregulated carbon emissions.”

France prepares for heatwaves of 25 °C (77 °F) mid-winter

France is experiencing record-high temperatures for this time of year, particularly in its southern regions. It’s exactly the type of event amplified by global warming, meteorologists explain.

It’s almost beach weather in Southern France. In February.

Several cities across France are reporting temperatures of 24°C-25°C (75-77 °F). Biarritz and Saint-Jean-de-Luz, two cities close to the ‎Pyrénées Mountains, as well as Tarbes and Perpignan are reporting record heat for what is supposed to be a winter month.

The heatwave comes in the context of an already mild winter. François Jobard, a meteorologist forecaster at Météo-France said that this is an “abnormal event”, marking the second-hottest start of February since 1900. Simply put, these are temperatures you’d expect to see in June, not February.

The warm wave of air is coming from the Azores and the subtropical Atlantic area, Jobard explains. While a cold spell is likely to follow this unusually warm period, it seems that the winter will continue to be relatively warm.

“We will continue to see temperatures that are higher than the normal average. This does not rule out several short, colder periods, but the trend will stay mild. After this peak of warmth, we will see a maximum on Monday (February 3), but on Tuesday (February 4) temperatures will cool down noticeably and be closer to normal.”

It’s always difficult to pinpoint singular events as being caused by global warming. However, this is exactly the type of event you’d expect to become more common as our planet continues to heat up. In Perpignan, the average high temperatures in February are around 12°C (54 °F), and they’re usually recorded towards the end of the month. Temperatures in Perpignan are expected to reach 26°C (74 °F) today.

It’s not just that global heating is driving up temperatures worldwide, but it is also causing imbalances in global wind circulation. Our planet heating up is causing heatwaves (and even cold spells) to become more frequent, so it’s much more likely to see temperature spikes such as the ones in southern France in the future.

“Overall we have warmer air masses than before, so with an equal meteorological situation, we tend to beat more records of smoothness than in the past “, Jobard concludes.

Scientists are concerned that the unusually warm weather might also trigger avalanches in the Alps.

Climate change action requires big changes, new report highlights

Every bit of policy now needs to be refreshed, says one of the authors of the new report. It’s the government’s job to tell the public that small and easy changes will not suffice, the report also mentions.

Researchers from Imperial College London have been working on a report advising the UK’s ministers how to reduce the country’s carbon footprint. The report is meant to advise on how the country can respect a recently-passed law which obliges the UK to achieve net zero emissions by 2050. It is basically a to-do list for the government, followed by an assessment of how things stand at the moment, and how they can evolve in the future.

While the report is not public at the moment, journalists from the BBC have seen the report and have described its contents. While the report is tailored for the UK, the general takeaways are valid for the entire developed world.

Taxes for carbon — not subsidies

“Every bit of policy now needs to be refreshed,” warned Chris Stark, the Chief Executive of the Committee on Climate Change, in an interview with the BBC.

For starters, subsidies for fossil fuels have to go. According to the International Monetary Fund, the world offers a whopping $5.2 trillion a year in subsidies for the fossil fuel industry. We can’t transition to a low-carbon economy if we don’t tax carbon-producing industries, and subsidies for fossil fuel simply have no place in a low carbon economy — UK or otherwise.

Furthermore, taxes on low-carbon technologies must be cut to encourage their emergence. Taking subsidies from the fossil fuel industry and moving them towards renewable energy is a potential approach.

Lastly, the infamous carbon tax must be applied — in one form or another. Leading economists are already calling for a carbon tax, which makes simple economic sense: carbon is a negative externality, it produces damage supported by a third party (the entire society), and must therefore be taxed. This doesn’t necessarily have to be a direct tax. There are several ways to tax carbon, but in some form, this must be implemented.

“These changes need not be expensive or reduce well-being,” the report concludes, “but they will not happen at the pace required unless policy first removes obstacles to change in markets and consumer choice.”

Carbon taxes have proven to be politically unapproachable so far, and some don’t believe them to be a good idea, but the report highlights this as an important part of the decarbonization process.

Diet & home heating

While the former problems are mostly about policy, the report also highlights changes for the rest of us — starting with our diet.

Plant-based foods should be on every eco-friendly plate.

Worldwide agriculture has become a massive contributor to global emissions, and researchers recommend switching to low-carbon diets — which basically means more plants, less meat. Already, numerous studies have published similar conclusions: one of the best ways to reduce your carbon footprint is to eat less meat. This is better for the environment, better for the animals, and better for your health.

Another aspect discussed in the report (and particularly relevant in the UK, where many houses are old and non-insulated) is home heating. The report has a whole catalogue of policy recommendations here, but the bottom line is that we need to transition to low-carbon heating systems (such as air-source heat pumps, which absorb heat from the outside and then use it to heat the house). Pricing gas higher than electricity can also help in this regard.


We can’t really talk about reducing greenhouse gases without discussing transportation. Favoring public transportation and cycling/walking should be done with urgency. This means investing in the bus and train network, as well as developing infrastructure for safe cycling (which is missing in many parts of the UK and the world).

Switching to electric cars is also an important aspect here, the report acknowledges. In this regard, researchers urge for larger subsidies for electric cars. A smart technology is also highlighted for electrical cars: smart EV charging systems. This would encourage drivers to recharge their cars when electricity is cheap or when renewable power is plentiful. This too would require important investments in infrastructure.

Lastly, flying is also addressed. An important part of most households’ emissions comes from flying, but the average is misleading here: 15% of the population is estimated to take 70% of flights. The report recommends focusing these frequent flyers and develop a policy that taxes them — not the family who is flying once per year on vacation. As a first step, the researchers suggest stopping air miles and frequent flier reward schemes and offering passengers more information about the emissions generated by flights.

The bottom line

None of these changes are easy. They will require substantial efforts from every one of us, as well as healthy and timely policies.

“If the public are to become engaged with the climate challenge and contribute to achieving net-zero emissions then the wider policy context will also need to be more supportive. New, compelling narratives will be needed to inspire and mobilise mainstream participation in solutions, adoption of technologies and change in behaviours,” the report concludes.

“Government must create a wider context which nurtures public engagement with action on climate change and must also enable consumers to take specific concrete actions that deliver large emissions reductions.”

However, these changes don’t need to be expensive — they could even save a lot of money in the long run. But timely action is essential, especially on the policy side, the researchers conclude. It’s up to us to support politicians in favor of such actions.

The findings can be read here.