A rising tide lifts all boats?

The terms ‘climate change’, ‘greenhouse effect’ and ‘limiting CO2 emissions’ are bounded around so often these days from the media, political spheres and industry, but have we sufficiently questioned ourselves on whether we truly understand what they mean so that we can evaluate these things critically? I admit up until very recently to being in the ‘no’ response camp here so reading the initial two chapters of Houghton’s ‘Global Warming: The complete briefing’ was genuinely enlightening. Hopefully this first blog will help to cover these off so we have a strong foundation to build (and critique!) from.

So what is climate change?

Firstly, it is important to separate out climate change from the short term climate variations. We know how variable climates can be, using it to describe something ‘changing like the weather’. But I interpret the environmental term of Climate Change (which I’ll take the liberty of capitalising from here on in this blog only just for distinction from the ‘everyday’) to regard a sustained period of global change in climate, like the overall internal body temperature changes causing enzymes to denature if experienced for longer, not outward, passing changes, for example a chilly nose on Bonfire Night or hot feet in bed.

Human-induced (also known as anthropogenic) Climate Change is to what extent we can trace cause and effect from human activity , since we know there are other scientific or episodic occurrences causing Climate Change too. For instance, volcanoes are well known to turf out large amounts of carbon dioxide upon eruption and have the potential to enter the Earth into a cooling period with the amount of released gases blocking the sun. but even when considering an eruption of a super-volcano like Yellowstone (occurring on average once every 100,000-200,000 years) humans contribute at least the same amount if not more emissions every year (volcanoes are just one example factor in a natural greenhouse effect, but more on that later!)

And we’ve observed increased numbers and intensity of Climate Change related catastrophes in the last 40 years, particularly due to prolonged temperature change in line with human industrial incline. In 1998, one of the warmest years on record in terms of Earth surface temperature, countless climate irregularities or disasters took place across the globe. These ranged from severe droughts and soaring temperatures in the US incurring $8 billion damages, to extreme flooding in India, recording 2870mm rainfall between July-October. In North America very wet and cold conditions lead to huge crop losses late in the year and in the Caribbean the large tropical rainfall experienced there caused severe infrastructural damages.

Certainly, in recent times the insurance industry has had to shift its modelling dramatically for significant weather events, moving its thinking from $10 billion being extraordinary costs to a place now where this is considered pretty lightweight. Hurricane Katrina amounted to an approximated $200 billion damages in 2005 and data shows us that these catastrophic weather event costs are very much trending upwards.

Ok, but what does Climate Change ‘change’ and for who?

Besides what I mentioned above in terms of trade and structural impacts which are, in themselves, extremely serious in their potential to economically overwhelm countries, environmental events have been and are shocking in their fatalities. Heatwaves and droughts can result in premature human deaths often involving wildfire spread, famine or dangerous migrations. In 2010 Central Russia experienced heatwaves and wildfires that are reported to have caused 55,000 premature deaths. Extreme tropical cyclones or flooding wreak devastating effects on those in vulnerable areas, displacing millions from their homes and causing deaths from drowning. I’m sure as you read this you have in mind a poignant weather related disaster where you remember the staggering death toll being read over the news reports.

The ‘who’ aspect of this question is a difficult one, since climate change has a buffet of effects that are felt differently across the globe. That being said, from my reading I would settle on two general thoughts. 

The first is a simple one – geographical location matters. Storms causing inland flash flood surges will impact those living near to or in low-lying areas in relation to the coast. Rising sea levels caused by the heating and thus expansion of water have modelled much human inhabited land now to be under water by the end of the century, such as vast swathes of Indonesia. More and hotter heatwaves will continue in their fatalities, reducing biodiversity as conditions become unacceptable for species, as is already the case in parts of Australia to give an example. 

The second is complex and admittedly I only share a lightweight personal comment on this given less comprehensive research at this stage – developing countries are set to be most affected. This could be down to a wealth of factors; lack of resilient infrastructure, a large percentage of the population in poverty, less sophisticated monitoring technologies, localised economies heavily reliant on agriculture, to name just a few. I feel anxious in thinking about this, particularly as I consider the implications of ‘adaptation’ and ‘mitigation’ strategies and whether the investment choices for these will advantage or disadvantage developing communities.

Hang on, what is adaptation and mitigation?

Put simply, adaptation is activities carried out in order to reduce the effects of Climate Change, such as cloud seeding and flood defences, whereas mitigation involves activities aiming to reduce the causes of Climate Change, such as planting trees or reducing energy consumption. Therefore, a scenario by which the West heavily invests more in adaptive over mitigation initiatives may leave developing countries behind, unable to match this investment unless otherwise internationally funded. In any scenario however, as Houghton comments, we will already have to effectively adapt to the fallout of existing emissions over the next few decades at least, even if we should miraculously stop all our CO2 emissions tomorrow and reduce the enhanced greenhouse effect.

But what is the greenhouse effect and what is ‘enhanced’ about it?

The term ‘greenhouse effect’ sprung up in the early 19th Century, coined by the French scientist Jean-Baptiste Fourier who made the initial connection between our atmospheric activity and that of a greenhouse. We can break it down into two main concepts: radiation transfer and convection. 

1. Radiation transfer – solar radiation is transferred to the Earth’s surface, of which 50% is absorbed and heats the surface. Some of this is emitted back out, where CO2, water vapour and other greenhouse gas contributors are strong absorbers, acting as a warming blanket around the Earth. 
2. Convection – We all know hot air rises. This is because it is less dense. Air closest to the surface is hotter given its proximity. Simultaneously, cold, denser air falls. As the hot air makes its way to the upper parts of the Earth’s atmosphere it cools and makes the absorbing gases less able to emit the radiation, or in other words more absorbent.

These processes occur naturally (surprisingly called the natural greenhouse effect). Expanding on this further is ‘runaway greenhouse effect’, whereby a lot of naturally occurring water vapour in a planet’s atmosphere would heat the planet’s surface due to radiation absorption, thereby causing more evaporation and more water vapour in the atmosphere, repeating and repeating until the atmosphere was full of water vapour or all previous water particles had been evaporated completely. This may have been what happened on Venus. Due to it being closer to the sun and therefore hotter than Earth, it began its life with a surface temperature of 50°C. Hence surface water would always be at boiling. This lack of water equilibrium, i.e. balancing water vapour, liquid and ice forms, meant the planet eventually lost all its water as it evaporated out into space, getting hotter and hotter as the more vapour absorbed radiation. Poor Venus with its lack of thermostat!

Now back to what ‘enhanced greenhouse effect’ is; how this effect has been increased due to gases in the atmosphere being ejected by human means, namely CO2 emissions (given water vapour amounts are largely not a direct cause of human activity but rather ocean surface temperature) and also methane. CO2 levels have risen dramatically since the industrial revolution, releasing at least 800 million tonnes to existing carbon dioxide levels every year. Given exponential growth in our industry and population, this number will certainly explode without global commitments such as the Nationally Determined Contributions (NDCs) of the UNFCC Paris Agreement, requesting countries to lay out their Climate Change actions to curb greenhouse gas emissions.

Wrapping up…

Now having re-visited these terms with more rigour, it makes me think about not only the implications of our greenhouse gas emissions over natural carbon cycles but also who will be the future victims of this human induced Climate Change. I included the saying ‘a rising tide lifts all boats’ in the header because after having read Houghton’s article it made me see a dark irony to the saying. It is intended as an analogy for a growing economy leading to prosperous outcomes for all, but it is precisely this economy of large-scale human industrial activities that has been evidenced as hugely contributing to Climate Change and subsequent weather disasters.

Time for a sea change.

References

• Anon. What do volcanoes have to do with climate change? (no date) Unfccc.int. Available at: https://unfccc.int/process-and-meetings/the-paris-agreement/nationally-determined-contributions-ndcs (Accessed: October 19, 2022).
• Houghton, J. (2015) “Global Warming ,” Chapter 1 and 2, pp. 1–31.
• Kaplan, S. (2021) A runaway greenhouse effect turned Venus into ‘hell.’ could the same thing happen here?, The Washington Post. WP Company. Available at: https://www.washingtonpost.com/climate-solutions/2020/03/20/runaway-greenhouse-effect-turned-venus-into-hell-could-same-thing-happen-here/ (Accessed: October 19, 2022).
• McNeil, L. (2022) “can we engineer rain to help solve climate change?,” The Climate Question. BBC World Service.
• Munoz, L. (2017) ‘Seeding Change in Weather Modification Globally’, World Meteorological Organization, Available at: https://public.wmo.int/en/resources/bulletin/seeding-change-weather-modification-globally (Accessed: October 23, 2022).