Climate Change: Why the Numbers 450 and 7 Matter

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from 'Chasing Ice'
from ‘Chasing Ice’

Have you ever looked back at a situation and wished you’d had some key information? Those little bits of knowledge that would probably have led to a different decision? 

In the hopes of sharing some key info and fending off future regret, you might be interested in climate change’s two critical numbers: 450 and 7.  Paying attention to these two numbers and knowing their future impact on your life may influence decisions you make today, and possibly drive better outcomes tomorrow.

450 parts per million CO2, and We’re Cooked

You’ve heard a lot about the gas CO₂. It’s the gas known as carbon dioxide that’s emitted when the fossil fuels, oil, coal and natural gas, are burned. Though found in scant traces in our atmosphere, CO₂ appears to be the “control knob” that adjusts temperatures in our atmosphere. Our atmosphere is the planet’s parka that keeps earth livable. (Venus’ average temp is 864º F. Mercury, stage left, is 862º F on the sunny side, and -252º F on the chilly side.)

CO₂ levels hovered around 280 parts per million (ppm) going way back and long before mankind began inhabiting the planet about 12,000 years ago. But when humans discovered coal in the early 1700s, we also discovered that burning fossil fuels emits CO₂. Since the Industrial Revolution in the 1750s, carbon dioxide levels have climbed from 280 to 400 ppm. 

Courtesy National Oceanic Atmospheric Admin.
CO₂ parts per million in our atmosphere exceed 400. The bummer is the rate is increasing every year-we’re collectively pumping out more.

Many scientists think that a “safe operating space for Earth” is 350 ppm. We blew through that figure when the the Pet Shop Boys’ “West End Girls” was the #1 song in 1986.  Since 1750, average global temps have risen 1.4 degrees, according to NOAA.

Even this modest temperature increase has had profound impacts on our polar glaciers. If the atmosphere is a parka, then glaciers are the planet’s air conditioners. Check out this condensed video of the riveting Chasing Ice documentary. Time lapsed cameras snapped pictures over several years of our planet’s retreating and melting glaciers. It’s incredible to watch, and they are melting faster than expected

Here’s the key factoid: Scientists also predict that to give our planet a 50/50 chance of staying in our current climate, we need to keep the temperature rise to two degrees. Put another way, CO₂ levels can’t exceed 450 ppm.

According to the latest United Nation’s International Panel on Climate Change (IPCC), if we don’t pass 450 ppm of CO₂, scientists assert we have a 50 percent chance of, “not crossing a critical threshold when a global climate changes from one state to another state.” If we exceed the threshold, the effects can be “irreversible,“ the panel states.  Yikes.  

Unlucky 7

One of the challenges in building global warming awareness stems from the people who write the reports, and that issue is exacerbated by those who don’t report the findings. Our world’s brilliant IPCC scientists write brilliant reports. Yet, not only are the reports tough to read, but media outlets often shy away from global warming stories because they’re controversial and not on a news cycle. Climate change is a slow burning story, similar to diabetes rates and national deficits. 

Buried in the latest IPCC report is the “gotcha” graph below that predicts global temperatures. If “we” do nothing to reduce greenhouse gases, North America’s average temperature is forecasted to rise between 2081-2100 to a minimum of 7º F. That’s hot. 

Found on page 10 of the IPCC summary report, The yellow graph on the right reflects predicted global temps is we do reduce GGH, the “hot red” graph on the right is the “do nothing” scenario.
Found on page 10 of latest IPCC summary, yellow graph on left reflects predicted global temps if we reduce GGH. The “red hot” graph on the right is the “do nothing” scenario.

A PhD isn’t needed to surmise that with elevated temperatures, we will probably experience an unpredictable climate where everything will be impacted: food production, drinking water reserves, daily weather, droughts, sea levels, ocean temps, animal species, plant species, the list goes on and on. We’re seeing climate change’s impacts today with the strangest weather, psycho storms and droughts.

OMG. What do I do?

1. Pay attention.

Stay aware of climate change. It’s not going away and it’s not far off. At the increasing rate we’re collectively pumping out CO₂, my simple excel chart predicts we’ll hit 450 ppm in 2030. That’s only 15 years. Stay informed. Read our green posts on Baltimore Fishbowl, and consider subscribing to the Huffington Post’s Green site newsletter for daily green news.  For readable and interesting climate news from a scientist, check out Joe Romm’s (PhD in physics from MIT) Climate Progress blog. 

2. Become a responsible consumer

Buy less. Buy organic. Buy renewable. The easiest and biggest change is to switch to a climate-friendly electricity and natural gas supplier through BGE. Click here for a step-by-step guide. This 5-minute online change is often priced on par with “dirty” energy. Caveat: Do not pick a flexible price per month option. Only choose a fixed and locked in 1 or 2 year rate contract. Washington Gas Energy Services is a reliable, local supplier that’s been offering both climate-friendly electricity and natural gas options for years. Buying green energy can chop your carbon footprint by almost half.

3. Be mindful and reduce your energy

You’ve heard the how-to-be-green-to-do-list before, but it makes a huge difference. Plug up your leaky and energy hog home. Switch the incandescents lightbulbs. Buy a fuel-efficient car. Recycle everything.  You can reduce your household energy use, have the same modern life and save money. It’s just focus. 

4. Vote for environmentally-minded politicians

Here’s the tough one. The newly elected House and Senate, for the most part, don’t buy into climate change. The Senate’s first order of business this week is to vote on the Keystone XL pipeline. Why? Exxon and other U.S. oil companies want to lower their tar sands’ oil transportation costs; pipes are cheaper than trains. Fracking, deep water drilling, tar sands oil and mountain top coal removal just fuel global warming. The companies that undertake these fossil fuel projects also fund many politicians’ campaigns. 

5. Stay positive. Get green, sustainable, whatever. Renewable is Doable

Led by Stanford University’s Solution Project, there is a reality-based movement illustrating that transitioning from fossil fuels to sustainable sources of energy is possible. Did you know there is plenty of wind and sun to fuel our world forever? Check out the group’s prediction for how Maryland gets 100 percent sustainable energy. 

It seems a smart time to embrace being green, not as a “crunchy niche cause,” but as a save-our-butts kind of idea. Many of us will be above ground when more of climate change’s impacts hit home. The idea isn’t to return to the Middle Ages, but to create a modern world that is fueled by energy that won’t cook us alive. 

Laurel Peltier
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  1. Outstanding, straight-forward piece that boils down essential information on climate change! There are things we can do right now and the sooner we get going the better.

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