Are the effects bad?

So let’s say we accept that the earth is getting warmer. So what? The change sounds so small, and maybe that increase even seems welcome come mid-winter in, say, Minnesota. It is a mistake to think that way as:

• The rate is much higher in many regions, and the change is accelerating. The 1.8 °F is the global average change over a long period. However, it is more than that in different regions (particularly the northern hemisphere), and the rate of increase is itself increasing. From the Berkeley Earth site [2], we can see that whilst the average rate of change of temperature worldwide since 1810 is 0.79 °C/century, since 1990 it is more than 3 times that at 2.78 °C/century. But the rate is much higher in Canada, at 6.5 °C. That means Canada is heading for a further significant increase of over 9 °F by the end of the century, even if the rate doesn’t accelerate further.

• The impacts are global. It would anyway be morally reprehensible to enjoy milder winters in Minnesota at the cost of mass flooding elsewhere, but if global food supplies are impacted, it will anyway undermine that benefit!

So let’s look again at the key reports from the US government and UN that details the effects being seen, and some predictions.

From highlights from the executive summary of US governments NCA4 Vol1 [3] :

• Rising sea levels: Global average sea level has risen by about 7–8 inches since 1900, with almost half (about 3 inches) of that rise occurring since 1993 (about 1/8th inch per year). The incidence of daily tidal flooding is accelerating in more than 25 Atlantic and Gulf Coast cities.
• Increased extreme weather events: The frequency and intensity of extreme heat and heavy precipitation events are increasing in most continental regions of the world. These trends are consistent with expected physical responses to a warming climate. For example, the chart below shows the % change of the number of occurrences in unusually heavy rain (defined as 2 days where the rainfall at a level that would only generally expect once every 5 years). So in the last 58 years, the rate of heavy precipitation events has increased >40%.

• Oceans becoming acidic: The rate of ocean acidification (due to absorbing ¼ of CO2 emissions) is unparalleled in at least the past 66 million years.
• Shrinking arctic: Since the early 1980s, annual average arctic sea ice has decreased in extent between 3.5% and 4.1% per decade

Vol II of that same report looked specifically at the impact & risks for the US. selections from the summary of findings [4] . Expected impacts include:

• Infrastructure destruction and economic impacts: growing losses to American infrastructure and property that impede the rate of economic growth.
• Food supply: declines in crop yields and quality, with changes in extreme events threatening rural livelihoods, sustainable food security, and price stability.
• Droughts/floods/reduced water supply: more intense droughts, increased heavy downpours, reduced snowpack, and declines in surface water quality, with dependable and safe water supplies for parts of the US being threatened.

The breadth of impacts explains why the term “climate change” is now more generally used rather than “global warming”. The world is warming overall, disrupting the global climate, and one region might experience longer and more severe droughts, whilst another experiences 100 year floods on a regular basis. Some regions might even cool, due to shifts in the normal patterns of ocean currents.

This is not the only government agency warning of threats to the US, From the 2014 Homeland Security Review [5] (by law this should be updated every 4 years, but there seems to be nothing from 2018):

Weather events present a significant and growing challenge. The risk of these disasters is increased by the vulnerability of aging infrastructure, increasing population density in high-risk areas, and—in the case of droughts, floods, and hurricanes—by trends associated with climate change.

Climate change and associated trends may also indirectly act as “threat multipliers.” They aggravate stressors abroad that can enable terrorist activity and violence, such as poverty, environmental degradation, and social tensions. More severe droughts and tropical storms, especially in Mexico, Central America, and the Caribbean, could also increase population movements, both legal and illegal, across the U.S. border.

Certainly the international consensus is that a warming planet is very bad - that is why every country in the world, including the US, adopted the Paris Agreement in 2016. This agreement brings all nations together into a common cause to address climate change, by reducing greenhouse gas emissions so as to limit global warming to well below 2 °C by the end of the century, and to pursue efforts to limit further to 1.5 °C. (remember - we are already at 1°C) Each country sets it’s targets to meet that goal.

Since the Paris Agreement, there has been a subsequent IPCC report [6] that looked specifically at the likely effects of a rise of 2.0 °C, as opposed to 1.5 °C. I find this report less readable than others - it can be somewhat summarized as “1.5 °C is bad - 2 °C is much worse”. The chart below conveys the reports assessment of the level of risk of different kinds of impact, for varying temperature rise. So for example, whilst for warm-water corals even the existing 1 °C starts to move us into the “severe/widespread impact” (as we already see in corals around the world), it is somewhere between 1.5 °C & 2 °C that there will be severe/widespread impact on crop yields.

Of course, we can also see things with our own eyes. Close to home, fires raging each year in California (with the town of Paradise being erased in the 2018 Camp Fire that killed 85 - do we need more of a sign than “Paradise” burning down?). This year power had to be shut off to 1000s of people in parts of LA to reduce the risks of fires - we are the world’s leading nation and we can’t even keep the lights on! Here in my hometown, the last few years have seen Seattle clouded in smoke from fires burning up in Canada. This is not about forest management - we are seeing the same worldwide. Last year Sweden had their most serious forest fires in history, due to the long drought. As I write this, Sydney is blanketed in smoke as fires burn around New South Wales, with the fire chief making it clear that the issue is ever narrower windows when controlled burns can safely be carried out, due to rising temperatures and drought. Meanwhile, Venice is experiencing its worst floods in 50 years, and India had its worst monsoon in 25 years with the resulting floods displacing 1 million people. This is following on from the 2017 Mumbai floods, with 18 inches of rain in 12 hours. Hurricane Sandy, the largest diameter Atlantic storm on record, is estimated to have killed 117 people, and left 8.5m without power.

And we see natural wonders like the Great Barrier Reef fading before our eyes.

At this point, climate change deniers will be screaming that you cannot put down single events, like a devastating, fire, flood or a hurricane, to climate change. Quite right, you can’t. But let’s not get confused:

• Scientists predicted that a warming earth will increase frequency and intensity of such events.
• The earth is getting warmer.
• The frequency and intensity of such events is increasing.
• The extent of human suffering brought about by such events is clear, as is the fact that there is no hiding from it, and when they occur we are pretty much powerless to control.

So as we look at any one awful event, we can’t say “that was because of climate change”. But we certainly can reflect on whether we want to be increasing the frequency and magnitude of such things. And bad as the recent fires, floods and hurricanes have been, the scale of human misery, and the breadth of impact across the world, will only worsen if/when food supplies become severely impacted, and mass migration occurs from regions that are increasingly uninhabitable.

To fully understand the threat, we should also consider this in tandem with the environmental damage globally as a result of changing land use. For example, as I write this the Amazon is on fire, not because of climate change but because those fires are being deliberately set to clear land. However, they certainly contribute to climate change, as well as bringing other negative impacts in their own right. Two recent reports covering this are the IPCC special report “Climate Change & Land” (less readable than other IPCC reports, I found) [17] , and the UN report “Global Assessment on Biodiversity” [18] (from the UN group IPBES [19] ), released in May 2019. The latter report has a good summary from the BBC here and National Geographic here, and warns that we are facing huge loss in biodiversity, with 1m species threatening extinction within decades, with 1 in 4 species of animals and plants. Whilst climate change is a driver, the effect of land use has an even greater effect.

Finally, we have the potential for hitting a tipping point, beyond which we won’t be able to stop it. There are certain physical effects of warming that lead to positive feedback loops:

• Permafrost (permanently frozen land) is melting, and as it does so methane (a very potent greenhouse gas) that has been trapped 40,000 years pours out into the atmosphere;
• As the polar ice caps and world’s glaciers shrink, the amount of radiation they reflect back diminishes, resulting in more heat being absorbed;
• Much of the CO2 that gets released into the atmosphere gets absorbed into the oceans. However, warm water can absorb less CO2 than cold water, so as the oceans warm, they can absorb less CO2, leaving more in the atmosphere to lead to more warming.
• Trees and other plants absorb CO2. Deforestation, whether intentional or resulting from more frequent forest fires from drought, reduce the amount of CO2 being absorbed (not to mention the CO2 obviously released by the fires we have seen raging across the US, Europe, and Australia).

So this is not something that we should start thinking about soon - this is something we need to be acting on across the board now.

Of course, the other way of making this clear is simply to examine what leaders in the US and worldwide have said (avoiding Democratic leaders like Obama and Gore who seem to stir up bile among some!) When you encounter someone arguing against urgent action on climate change - your uncle saying it’s all due to solar flares, your neighbor saying it’s all ok because more people are buying electric cars now (and would you like to see his new Tesla?), or some nutjob on the internet claiming it’s all part of a conspiracy for the government to seize more control - imagine the three of them in a roomful of the following people and decide who you are going to bet your kids future on!

• Bill Gates, Founder of Microsoft Climate change is a terrible problem, and it absolutely needs to be solved. It deserves to be a huge priority. [20](Bill is also, of course, putting his money where his mouth is)
• Spencer Dale, chief economist of BP (global energy company) The world is on an unsustainable path.The longer carbon emissions continue to rise, the harder and more costly will be the necessary eventual adjustment to net-zero carbon emissions
• Tim Cook, CEO of Apple Humanity has never faced a greater or more urgent threat than climate change — and it’s one we must face together. [21]
• Kofi Annan, Former Secretary-General of UN The world is reaching the tipping point beyond which climate change may become irreversible. If this happens, we risk denying present and future generations the right to a healthy and sustainable planet – the whole of humanity stands to lose. [22]
• Executives of more than 70 companies (Apple, Google, Microsoft, Tesla,, Salesforce, Virgin Group, HP, Adobe, IBM, Verizon…) There has been progress, but not enough. This moment calls for greater, more accelerated action than we've seen. It calls for the strong policy framework the Paris Agreement provides… (from letter urging US to stay in Paris Agreement) [23]
• Elon Musk (though he would, right?:) We're running the most dangerous experiment in history right now, which is to see how much carbon dioxide the atmosphere can handle before there is an environmental catastrophe. [24]
• Satya Nadella, CEO of Microsoft The economy…, the capitalistic system... , will fundamentally be in jeopardy (on the day he announced Microsoft will be carbon negative by 2030)
• Jeff Bezos, CEO of Amazon Anybody today who is not acknowledging that climate change is real — that we humans are affecting this planet in a very significant and dangerous way — those people are not being reasonable. (Jeff has established Bezos Earth Fund, with $10 billion of his money)
• Emmanuel Macron, President of France By polluting the oceans, not mitigating CO2 emissions and destroying our biodiversity, we are killing our planet. Let us face it, there is no planet B. [25]
• John McCain We have many advantages in the fight against global warming, but time is not one of them. Instead of idly debating the precise extent of global warming, or the precise timeline of global warming, we need to deal with the central facts of rising temperatures, rising waters, and all the endless troubles that global warming will bring. We stand warned by serious and credible scientists across the world that time is short and the dangers are great. The most relevant question now is whether our own government is equal to the challenge. [29]
• Pope Francis Global warming continues, due in part to human activity ... to commit a crime against the natural world is a sin against ourselves and a sin against God [30]
• Desmond Tutu, Former Archbishop of Cape Town Twenty-five years ago people could be excused for not knowing much, or doing much, about climate change. Today we have no excuse. [31]

It is the last quote from Desmond Tutu that most resonates with me - we have no excuse for not knowing - no one in the US today can claim they were misled, or not told. So what’s our excuse for not acting? Our kids (or grandkids, if you have them) might well be facing dire consequences themselves, or helplessly watching them unfold elsewhere in the world, and they will reasonably ask our generation why we didn’t act. I want to be able to get to sleep with my answer to that question.