The Science of Climate Change 101

I am planning to write a series of articles to delve deeper into the problem of climate change.

What is Climate Change? Most people have an unclear understanding of Climate Change. In layman terms, it’s the long-term alteration of temperature and normal weather patterns.

The Paradox of Rational choice in Climate Change: It may seem individually irrational to take action in the face of climate change due to personal costs and small effect, and even though it is collectively rational to take action.
The importance of change at the individual level, however, is far greater than most people recognize, and such change when taken up by billions will make a decisive difference.

How is it caused?

1. Planetary Reasons: Total solar irradiance is the total output of light energy from the Sun, measured at the Earth. The seasonality and location of solar irradiance that the Earth receives is dependent primarily on three cyclic processes labeled “Milankovitch Cycles” that cause long-term climate variations.
2. Increased greenhouse gases (absorbs heat): 92% of the greenhouse gases are carbon-based — that’s why everyone keeps mentioning terms like ‘carbon footprint’ or ‘decarbonization’.

How do we measure climate change? We consider factors across air, land, and the oceans. There are 5 vital signs which are usually talked about:
- Atmospheric Carbon Dioxide
- Global Temperature
- Arctic Sea Ice Minimum
- Ice Sheets
- Sea Level

Source: https://climate.nasa.gov/vital-signs/global-temperature/

Why it’s an important issue? To prevent the worst effects of climate change, we need to get to zero net greenhouse gas emissions in every sector of the economy within 50 years — and as the IPCC recently found, we need to be on a path to doing it in the next 10 years.

• Submerging coastal cities: Glaciers are melting and water is going into oceans — which will lead to extreme sea levels in coastal cities.
• Groundwater Crisis: The groundwater scarcity have already reached alarming rates in cities like Chennai and Bengaluru.
• Extreme Natural Calamities: higher evaporation rates lead to more droughts, more water vapor in the air provides “fuel” for more powerful storms to develop, increased heat in the atmosphere and on the ocean’s surface intensifies tropical storms. Infrastructural safety measures of many affected areas have proved ineffective.
• Health Problems: Increasing heat waves, warmer conditions increasing risk of virus outbreaks.
• Social divide: Those who have less that will suffer more. Those who have contributed least to emissions may end up bearing the heaviest burden.

So, now we have to understand which are the main sources of carbon to the atmosphere and figure out non-carbon alternatives to those activities and deploy them economically at scale.

The 5 Grand Challenges

1. Electricity (25%). Renewables are getting cheaper and many countries are committing to rely more on them and less on fossil fuels for their electricity needs. But, we still need more breakthroughs.
   — Storage: Wind and solar need zero-carbon backup sources for windless days, long periods of cloudy weather, and nighttime.
   — Making the electric grid a lot more efficient so clean energy can be delivered where it’s needed, when it’s needed.
2. Agriculture (24%). Cattle are a huge source of methane; in fact, if they were a country, they would be the third-largest emitter of greenhouse gases! Out of this 24%, 18% is due to animal agriculture, that is why we hear the ‘vegan movements’. It’s pretty simple to understand — an average cow
3. Manufacturing (21%). Look at the plastic, steel, and cement around you. All of it contributed to climate change. Making cement and steel requires lots of energy from fossil fuels, and it involves chemical reactions that release carbon as a byproduct. So even if we could make all the stuff we need with zero-carbon energy, we’d still need to deal with the byproducts.
4. Transportation (14%). Low-emission cars are great, but cars account for a little less than half of transportation-related emissions today — and that share will shrink in the future. More emissions come from airplanes, cargo ships, and trucks. Right now we don’t have practical zero-carbon options for any of these.
5. Buildings (6%). Do you live or work in a place with air conditioning? The refrigerant inside your AC unit is a greenhouse gas. In addition, it takes a lot of energy to run air conditioners, heaters, lights, and other appliances. Things like more-efficient windows and insulation would help. This area will be more important over the next few decades as the global population moves to cities. The world’s building stock will double in area by 2060. That’s like adding another New York City every month for 40 years.

(The final 10% is a sixth, miscellaneous category that includes things like the energy it takes to extract oil and gas.)

Another Important Factor to consider:
Plastics: The conversation surrounding plastics doesn’t quite seem to fit into the climate box, although every single stage of plastics production, usage and disposal contributes in some way to carbon pollution. As plastics accumulate in landfills, they release fragments and toxins into groundwater that is highly detrimental to agriculture. Plastic debris in the oceans is easily ingested by marine life, poisoning them and potentially causing death. Microplastics — plastics that have broken down into microscopic particles — have pervaded oceanic waters as well, making removal solutions infinitely more difficult.

Projects like The Ocean Cleanup aim to tackle this by trying to remove plastic waste from the Great Pacific Garbage Patch, the world’s largest oceanic gyre of plastic.

Energy is core to nearly every part of your life: the food you eat, the clothes you wear, the home you live in, the products you use. We go to the supermarket and take the things for granted as if the supply is infinite — but the things that go behind the picture play a major role.

We’re always told to save more electricity/water at homes yet it’s just the 5% of total while animal agriculture is 55%.

The normal life is run by algorithms of marketing but a normal person never thinks what happens behind the scene. A simple example, the water required to prepare 1 hamburger equals 2 months of a human shower. Most of our land and food is being used to breed animals. 91% of Brazil’s deforestation has been caused due to Animal Agriculture.

Individual Action & What can/is being done

• Transportation: using hybrid or electric cars, ride-share services, choosing public transportation, or riding bicycles as a means of transport all contribute to reducing emissions. Another vector for transportation-related solutions is removing the need to travel at all — this is where remote work innovations such as video conferencing and virtual workspaces come into play.
• Food and Waste: with close to a third of the world’s food production — around 1.3 billion tons — being wasted in 2018, it is clear that food waste is a problem that is far bigger than it needs to be. Policy and industrial solutions exist that could drastically reduce waste produced along the food supply chain, but personal solutions such as not overbuying groceries, household composting, understanding expiration dates and repurposing vegetable scraps are viable ways of reducing waste on an individual scale.
• Energy and Materials: while large-scale solutions such as wind and solar farms may come to mind, a variety of individual solutions can effectively reduce household energy usage. For households located in areas with optimal weather conditions, rooftop solar and micro-wind solutions could provide partial clean energy solutions, while switching to energy efficient lighting (e.g. LED) and installing smart thermostats are more widely applicable solutions.

Appendix: Some more facts related to Climate Change

https://www.ipcc.ch/report/ar5/wg3/

Resources: Amasia Articles | Gates Notes