Luke Hansford


Climate emergency

🌱 Seedling10 min read

Current situation

As of 2023, the actual policies being implemented by governments puts us on a path to 3.3°C warming by 2050.1 On top of this, it's believed that emissions are underreported by 23%, which is not accounted for in the above number. It also doesn't account for reduction of photosynthesis as the globe warms (photosynthesis has an upper heat limit).

Our budget for staying within 1.5°C has become so vanishingly small, it’s likely we will overshoot this budget no matter how fast we reduce our global emissions. 2°C is achievable, so long as countries actually implement climate policies they've committed to and focus on changes they can make in the near term as opposed to out in the future.

The Swerve

Focus on the swerve. Believe it or not, the swerve is a happy ending...All we've got left is the swerve. 2

Cory Doctorow talks about "The Swerve", i.e. the course correction we as a species need to make to stop our proverbial bus from driving off a cliff. "It won’t be nice", but it is our "most hopeful future"

Our happy ending isn't averting the disaster. Our happy ending is surviving the disaster. 2

Carbon offsets

Carbon offsets tend towards being scams. See this John Oliver episode for examples. I'm sure there's some nuance though, so it's something I want to research more.

Ethical travel

How to ethically travel is something that I'm still trying to figure out. As an expat I fly pretty frequently. When I lived in Europe, train travel was an option, but Phuket presents a challenge: no trains and bus and car travel is too far (roughly 900km to either Bangkok or Kuala Lumpur), not to mention the abysmal road safety record in Thailand, so flying becomes the default choice. On top of this I need to regularly visit family in Australia and Borneo, so again flying is the only option. Tim Bray makes good arguments that we should be shifting towards slower forms of travel, but unfortunately that isn't a possible choice for us yet.

Of course, I’ve just ruined everyone’s vacation plans because they don’t get enough time off work for this kind of extravaganza. Well, that’s a bug too. As is the notion that it’s ever a good idea to travel at one time-zone per hour. 3


See Impacts of climate change.

Tipping points

A tipping point is a threshold beyond which a tiny change could push a system into a completely new state, causing dramatic, irreversible, and typically catastrophic change. 4

Some examples are:

  • Greenland or West Antarctic ice sheet disintegration.
  • Loss of permafrost.
  • Amazon rainforest dieback.
  • West African or Indian monsoon shift.
  • Boreal forest shift.
  • Atlantic meridional overturning circulation breakdown (i.e. Atlantic ocean currents).
  • Coral reef die-off.

Tipping points are connected to carbon cycle feedbacks.

Responsibility for climate change


Discussions on the responsibility of different countries for global warming has led to the adoption of a core principle in global climate treaties called Common but Differentiated Responsibilities and Respective Capabilities (CBDR–RC).

The CBDR-RC principle acknowledges that the more industrialized a country is, the more it has likely contributed to climate change. As per this principle, each country's emissions reduction targets are to be set based on their historical contribution to climate change and their respective abilities to address the problem. 4

Under CBDR-RD, countries are divided into Annex I and non-Annex I. The former generally being developed countries and the latter being developing countries.

Loss and damage

Loss and damage refers to the toll of climate change on vulnerable countries—economic and otherwise. This can include extreme weather events like heatwaves and storms, as well as sea-level rise, and the people and countries hit hardest are often the least to blame. 4

While rich countries like the United States have a history of dragging their feet when it comes to such asks, in the waning hours of COP27 in Egypt, wealthier nations agreed to begin the process of setting up a fund to help vulnerable countries dealing with ever-worsening climate impacts, as NPR reports. 4

It's also worth noting there are arguments that poorer countries can’t reduce emissions because they need to grow their economies in order to fix poverty. Interestingly, one counter-argument here is that "the amount of energy needed for providing food, housing, cooling and heating, education, mobility, and more is much less than we are currently using," per research by Jarmo Kikstra (Twitter thread). And Carbon Tracker reports that eradicating extreme poverty globally would increase global emissions by less than 1%. 4

Efforts to fight climate change

Curbing greenhouse gas emissions quickly and at scale is core to stopping the planet from getting even hotter.

The only way to arrest climate change is to get to net-zero emissions: cutting greenhouse gas emissions to as close to zero as possible, with any remaining emissions re-absorbed from the atmosphere. 

Remember: Earth will keep getting hotter until we achieve net-zero emissions. It will then stay at that temperature for a long, long time, unless we can suck a huge amount of extra carbon back in. (Comparing Emissions)

There is a consensus that to avoid the worst impacts of climate change we need to keep the global average temperature at or below 1.5°C compared to the average temperature in the pre-industrial era, circa 1880. As of the end of 2021 we're between 1.1°C and 1.3°C.

The risks of compounding, catastrophic impacts greatly increase at temperatures greater than 1.5°C 4


Above 1.5°C, the potential for abrupt and unexpected shifts in the climate increases drastically.

The original momentum behind a 1.5 C target was political, and was led primarily by developing nations and small island nations before the Paris climate conference in 2015 4

Warming is likely to more or less stop once carbon dioxide emissions reach zero, meaning humans have the power to choose their climate future. 5

We must distinguish between stabilising CO2 concentrations at a given level as opposed reducing CO2 emissions to zero or net-zero. Stabilising concentrations would still lead to warming (about 0.5°C over the next few centuries), whereas reducing emissions to zero would cease further warming.

Net-zero implies that any remaining anthropogenic emissions are balanced by additional carbon removal efforts, meaning that no net CO2 is added to the atmosphere. 4


Climate change that has already occurred up until the point were we reach zero emissions will be difficult to reverse in the absence of large-scale net negative emissions.

Actions that prioritize emissions reductions today are more impactful than reducing emissions tomorrow or a year or ten years from now. 4


  • Mitigation, i.e. the reduction and elimination of greenhouse gas emissions.
  • Removal, i.e. removal of excess carbon from the atmosphere and storing it in a safe manner.
  • Adaptation

Net-zero commitments

In March 2021, 124 nations out of 202 surveyed have made net-zero pledges (The race to zero emissions, and why the world depends on it | UN News).



UN Emissions Gap Report 2022

We are on track for somewhere in the range of 2.8°C of warming with existing policies, and at best, 2.4°C to 2.6°C of warming by 2100, even after taking into account all country pledges (pledges = promises about the future, as opposed to actual policies in place today) toward climate mitigation. 4

COP27 in Cairo

After accounting for all updated country pledges after COP27 in November 2022, not a single country’s NDCs are 1.5 C Paris Agreement compatible. This means that assuming all policies are fulfilled, we are headed toward 2.5 to 2.9 C of warming, give or take. The UN Emissions Gap Report 2022 projects a slightly different but similar range.

State of global progress as of COP27
State of global progress as of COP27


IPCC's Sixth Assessment Report (AR6)

Released August of 2021, it definitively stated that human activity is warming the planet in a rapid and unprecedented way, and that this is already causing extreme weather. It narrowed the estimated Equilibrium Climate Sensitivity and temperature predictions. It also stated that without drastic reductions to greenhouse gas emissions we will likely reach 1.5°C of warming in next few decades and that it would require transformational changes to end the century below that threshold.


COP21 in Paris

Led to The Paris Agreement, a legally binding international treaty to limit temperature increases to below 2°C.

Resources to learn about climate change

Companies fighting climate change

  • Running Tide. Carbon capture in oceans using kelp.
  • Norrsken Impact 100. List of startups having a positive impact on the world (not all climate change related).

Organisations fighting climate change

  • Intergovernmental Panel on Climate Change (IPCC). This is a UN body for assessing climate change-related science. Definitive source on international climate research and policy implications (e.g. the AR6 report).
  • Client Earth. Fighting climate change through legal systems.
  • Climate Emergency Fund
  • United Nations Framework Convention on Climate Change (UNFCCC). Host of the annual Conference of the Parties (CoP). Brings nations together to decide on climate policy.
  • GreenWave. Network of ocean farmers.

Investing in climate change solutions

Job boards for climate change

Open source climate projects

  • Open Sustainable Technology. A curated list of open technology projects to sustain a stable climate, energy supply, biodiversity and natural resources.

Climate change education



  1. Emissions Gap Report 2022

  2. The Swerve 2

  3. Slow Travel

  4. coursework 2 3 4 5 6 7 8 9 10 11 12

  5. Explainer: Will global warming ‘stop’ as soon as net-zero emissions are reached? - Carbon Brief

Linked notes


No one has interacted with this page yet.