Week 14: Know Your Numbers
We all know the importance of an annual checkup. Each year, when we head in for our well-visit, the first step involves taking our temperature, blood pressure, heart rate, and breathing rate. These measurements are known as Vital Signs, and they provide a snapshot of our body’s most basic functions. Vital signs are critical in calculating our risk for disease, detecting underlying problems, and keeping our health on track. During a medical emergency vitals are monitored around-the-clock. You can’t manage what you don’t measure, which is why knowing your numbers is critical. This knowledge is equally important for monitoring the health of the Earth.
Planetary Vital Signs
For this week’s challenge, we’re going to spend some time getting familiar with some vital signs scientists now use to track the Earth’s basic functions.
Starting around 2015, scientists began to acknowledge a fresh approach was needed for assessing how our planet is changing. Four years later, a set of 31 metrics—now referred to as the planetary vital signs—was put into use. These key measurements paint a much more detailed picture of the Earth’s state of health. For this challenge, let’s focus on learning about the 6 main vital signs included in these checkups, along with a quick glance at the current status of each one.
Carbon dioxide (CO2) is a gas consisting of one part carbon and two parts oxygen. It is essential for plant photosynthesis. Since humans and animals depend on plants for food, photosynthesis is critical for the survival of life on earth. In addition to natural processes such as breathing and volcanic eruptions, human activities such as deforestation and burning fossil fuels are generating large levels of CO2. Scientists now understand that the build-up of CO2 in our atmosphere is creating a warming effect and changing the earth’s climate. Since the start of the industrial era in the 1750s, the amount of CO2 trapped in our atmosphere has increased by about 50%.
NASA provides a detailed explanation regarding why global temperatures matter, but in summary, there’s a “sweet spot” for maintaining a healthy, thriving planet. Since 1880, scientists have been monitoring the Earth’s temperature and have noted that beginning around the start of the industrial era, the Earth has started running a fever. The year 2020 is tied with 2016 for the hottest year on record.NASA
Arctic Sea Ice
Sea ice is frozen ocean water, and for most of the year it remains covered with snow. This bright snow-covered ice reflects sunlight back into space. Arctic sea ice keeps the polar regions of the Earth cool and ensures our global temperatures stay in a healthy range, but as temperatures rise sea ice is melting. Since the start of arctic sea ice tracking in 1979, September ice levels have been declining at a rate of 13% per decade.National Snow and Ice Data Center
Land Ice Sheets
Ice Sheets are the large masses of ice in Greenland and Antarctica that cover more than 20,000 square miles of the Earth. These two ice sheets contain more than 99% of the freshwater ice on Earth and keep our weather, climate and sea levels in balance. As global temperatures rise, our ice sheets are melting too. Since 2002, scientists have been tracking this retreat in land ice. Each year, the Antarctic ice sheet has been shrinking in mass by 152 billion metric tons and Greenland’s sheet has been losing 275 billion metric tons of mass.National Snow and Ice Data Center
In simple terms, sea level is a measurement of the average level of the areas of the planet covered in water. Around 250 million people on our planet live along the areas that border our oceans and seas, and any increase in sea level increases risk for devastating flooding. Global temperature, sea ice and land ice sheets all work together to keep sea levels in check; however as global temperature climbs and ice melts, sea levels are rising. Over the past 30 years, sea level has increased by over 102 millimeters and coastal flooding is becoming much more common across the globe.NASA
As greenhouse gases build up in our atmosphere, heat radiated from Earth’s surface can’t escape into space as freely as it used to. As a result, most of this excess heat bounces back to the surface and is absorbed by our oceans. This is leading to ocean warming and creating a whole mess of negative impacts, including the destruction of breeding grounds for marine fishes and mammals, more extreme weather events and sea level rise. In 2021, the ocean temperature was the hottest on record since data collection began in 1955.
Taking these planetary vital signs into consideration, along with an in-depth analysis of data collected from the other 25 signs, scientists are now declaring the planet is in a “State of Emergency”.
Now, more than ever, it’s critical we “know our numbers” so we can truly comprehend the urgency for transformative change. The faster we can work together as a global community towards sustainable shifts, the sooner we can build a better future that ensures future generations (and the Earth) can thrive.
Grab the whole family and learn about planetary vital signs through the visual medium of video!