Climate change. Global warming. Which is it?
Well, good question. As it turns out, it’s both. That’s because one causes the other.
Here’s the basics:
As global temperatures increase (“global warming”), it causes the general patterns of weather that happens in each area – it’s climate – to change. That’s a big deal because the animals that live in any given area lives there for a reason: easy to access food, shelter, ideal temperatures. But when the climate of an area starts to change, the animals living there find themselves in a less-than-hospitable area. What they’ve been accustomed to – like how much snow they get or when the first frost occurs – has changed, and so they change, too. They only have three options: acclimate, move, or die, and most are going to try to move.
And whether they can weather the new weather is hard to say (in more ways than one). This is also true of humans who have come to rely on things like certain crops being able to be grown in predictable areas in predictable ways. We’ll have to adjust because we don’t have any other places to go, and how smoothly that adjustment happens depends on the policies we enact.
This is why climate change, a scientific reality, is also a political issue.
Other Resources on Climate Change
NASA: What is Climate and Climate Change?
IPCC: Intergovernmental Panel on Climate Change
United Nations Framework Convention on Climate Change
Consensus Statements of Major Scientific Organizations
American Academy for the Advancement of Science (AAAS)
American Chemical Society
American Geophysical Union
American Meteorological Society
American Physical Society
Geological Society of America
The U.S. Global Change Research Program
U.S. National Academy of Sciences
Joint Statements
Joint Statement from the 31 Major U.S. Scientific Organizations to Congress
The Intergovernmental Panel on Climate Change
The National Academies of Sciences, Engineering, and Medicine
The Science (Simplified)
Understanding climate change starts with an understanding of energy.
The sun provides energy to the earth allowing for life to exist, and excess energy is reflected back into space. Thankfully, several types of gases in our atmosphere reflect this energy back to the earth, helping it retain its heat. These gases, known as greenhouse gases, have allowed the earth to have a hospitable climate. The amount of greenhouse gases in our atmosphere has a significant impact on earth’s temperatures – too low, and the earth cools; too high, and the earth warms.
Human industry since the mid-1800’s has begun releasing significant quantities of greenhouse gases, and most of the heat being released into space is being reflected back. As a result, the earth is heating at an unprecedented rate. We know this not only through measurements of greenhouse gases and temperature changes, but by the influence that it is having on life.
One major impact is that on ocean life.
The ocean absorbs approximately 90% of earth’s excess heat, and oceanic temperatures have been rising because of it. In turn, this affects oceanic life. One of the biggest impacts is on coral reefs: coral reefs are home to over 25% of oceanic life, they play a key role in all oceanic life. But coral reefs are easily stressed by temperature changes, and when the temperature gets too warm (or too cold), they undergo “bleaching”, which makes them very frail, and they often die. Coral bleaching is at an unprecedented rate, and reefs are suffering because of it.
The ocean suffers for another reason: not only does the ocean absorb excess heat, but it also acts as a “carbon sink,” and the ocean absorbs at least 25% of the carbon dioxide we release. This changes the pH of the ocean, making it more acidic. Even small changes in pH can be disastrous, and for ocean life, other dangers include dissolving shells and fragile, non-repairing corals.
Global warming is also affecting land life as well.
The home ranges of animals are shifting as are migratory patterns, and many are facing extinction as they lose access to favorable habitats. This affects the food sources that are available, diseases that emerge, and can shift entire biomes (turning woodlands into grasslands, etc.).
One of the most frequently discussed impacts of global warming is its impact on ice and snow. Increased temperatures result in decreased snow and ice cover. Not only does this impact land and ocean, but it also has a compounding effect on global warming. Snow and ice are very reflective; without them, the ground absorbs 4-6 times as much energy. As we lose snow and ice, the earth absorbs more heat, we lose even more snow and ice. Called the “Ice-Albedo Feedback,” this means that the amount of snow and ice affects earth’s cooling and heating more than any other land feature.
Climate change and the ocean • MBARI
Global warming is already having significant impacts on human life.
Not only are our food sources and living conditions changing, meaning that we will be relocating to areas more hospitable (see also here), but climate change is causing increased frequency and severity of major storms. Not only will that affect everyone living in impacted areas, but all industries dependent upon wildlife and environment – including tourism, fishing, and hunting – will be seriously impacted at a serious economic cost.
Global Trends
Impacts on Oceanic
- Ocean has been increasing in temperature, with half of the heat over the past 150 years occurring within recent decades (NOAA)
- Significant increases in sea level caused by melting ice and show: 8 inches since 1900, and double that rate since 1990. (IPCC)
- Ocean Acidification: Increases in carbon dioxide absorption acidifies the ocean, causing rippling effects throughout the oceanic ecosystem, destroying sea life and industries that rely on them (NOAA)
Impacts on Humans
- Extreme weather events, including heat waves, droughts, hurricanes, tropical storms, blizzards, and floods are becoming increasingly common and more intense (NOAA) (C2ES) (NCA)
- Many diseases are linked to environmental and climate changes, and scientists are predicting increases in diseases as a result of climate change (WHO)