Global Water Crisis


Nobody denies that Chennai has a water crisis, but some have asked us whether Chennai’s water shortage is attributable to climate change?  The short answer here is: yes. But, like anything in the world, the long answer is: it’s complicated.  Chennai’s water shortage is mainly attributed to two years of weak rains which are a result of changing patterns in the Asian Monsoon.  Certainly, population growth and imperfect water management are related factors as well – but it’s not as if Chennai is doing nothing.  For example, all buildings in Chennai are required to have rainwater capture system – but in a developing country it isn’t always possible for everyone to meet all regulations.

With regards to the monsoon, the issue here is complicated as well – but it is indisputably a form of regional climate change resulting from human activity.  Research shows that disruptions in the monsoon are partly the result of increasing global temperatures and partly the result of particulate pollution impacting cloud formation.  A fascinating article on this topic is available here: (

Furthermore, Chennai is just a concrete example of a larger problem.  Groundwater is getting dangerously low in many parts of India and 21 cities may run out of groundwater by next year.  The Himalayan glaciers, which provide water to 1.6 billion people, are already melting rapidly because of climate change — and may be impossible to save.  Water scarcity is also a major contributor to forced migration both within and across borders.

Bottom Line: Chennai’s water crisis shouldn’t be 100% attributed to global warming, but it is undisputably one of several factors that have created this terrifying situation.

Foods Threatened by Climate Breakdown

Food impacts

These foods won’t all go extinct but yields are already declining.  Read more here (1,2,3).

Agriculture will have to move with the weather — a terrifying prospect for farmers who own their land — and we won’t always be able to find the same confluence of soil and climate.  Weather patterns are shifting fast year-by-year and good soil builds up over centuries.

And this is not a problem for the distant future.  We are already experiencing food shortages and price increases – but the extent of these shortages will depend on how fast we reduce our emissions and the impacts will depend on fixing global inequality.  Even today we live in a world where some people starve and others throw out food in huge quantities.

The impacts of climate-change-driven droughts and natural disasters on small farms in Central America is not only disrupting food security — it is one of the key causes of the current swell of mass migration.

Financial Risk

Financial impacts

The quote we chose is from a 2019 Bank of Canada Financial System Review.  But what is scariest here, is how little we actually know about the economic impacts of climate change.  Even the report in question mostly just suggests that banks and companies should start measuring and reporting climate risk.

In our view, estimates of the economic impacts of climate change are completely unreliable.  Unemployment rates are constantly subject to debate and revisions — and in this case economists are measuring something that has ALREADY HAPPENED.  Why should we expect them to be able to predict the future?  Few economists foresaw the financial collapse of 2008 and the interplay of climate, society, agriculture and weather systems is a much, much more complex and unpredictable system.

Will the cost of increased hurricanes and wildfires be predictable?  Or will they trigger unforeseen problems like failures in the insurance industry or immense property devaluation in cases where rebuilding isn’t feasible?  How much are Miami, Osaka and Shanghai worth?  Because they are all expected to be underwater by the end of the century — at what point will real estate values reflect this fact more completely?

For more on the financial risks, read Mark Carney’s (formerly of Bank of Canada, currently Bank of England) speech on our cataclysmic failure to act.

Also, if you really understand financial markets, the fact that climate change is getting serious discussion in the reinsurance markets should get your attention.

Worse and Worse

Exponential impacts

We chose this quote, because it quickly encapsulates something many people don’t understand about climate change — the impacts come AFTER the emissions.  What we are seeing now, is the result of emissions from years ago.  Even if we went to zero overnight, we would have considerably more warming locked in.  We can’t stop emitting when things get too uncomfortable we have to stop BEFORE it’s too late.

Earth’s temperature mainly depends on how much of the sun’s energy is absorbed and how much is released into space.  Some sunlight — especially light that hits ice or clouds — bounces straight back to space.  Some light is absorbed and becomes heat.  Some of this heat also escapes into space — how much depends on the composition of our atmosphere.  Some gases like methane and carbon dioxide slow the escape of heat.  In 1910, CO2 levels in the atmosphere were around 300 parts per million — today they are over 400ppm.  If we look further back in history and we realize how unusual these CO2 level really are:


And we haven’t even felt the full impact of our current greenhouse gas levels yet. If we stopped emitting extra GHGs today, the earth would continue warming for years.  This is because ice melts slowly, and as it melts, it exposes more dark earth, which means less light is reflected straight back into space and more of the sun’s energy is absorbed as heat, which in turn melts more ice.  A warming planet will also release bubbles of frozen methane in the arctic permafrost and under the ocean.  This is already happening — and it’s happening ahead of schedule.

The other reason we chose this quote is that Peter Kalmus’ book Being The Change: Live Well and Spark a Climate Revolution is fantastic and everyone should read it.  It shows how reducing your personal footprint, mindfulness, appreciating the little things in life and political advocacy are all interconnected in a virtuous circle that will improve your life and the planet.


Without significantly upgrading global efforts to reduce emissions, we are on track for four degrees of warming.  With four degrees of warming, our world might look like this: 4 degree map

Much of our impact research is based on a 2 or 3 degree world, assuming that the IPCC models were accurate and that countries live up to their pledges — but over the past year — neither of those things have seemed particularly true.  This map is a compilation of findings from this 2011 journal issue devoted to imagining a 4 degree world.  Again, we at Climate Pledge Collective are not climate scientists, but we are both PhD Candidates and we know how to research — and what we have found is that there is very little certainty about how bad things will get or how fast it will happen.  So why risk it?