In November of 2018, the fourth National Climate Assessment was made available to the public. I have a stack of the executive summary with me in the motor home to share with anyone I meet that is interested.
The report was written by the U.S. Global Change Research Program (USGCRP) as a result of a Presidential initiative established in 1989 and mandated by Congress. The Global Change Research Act of 1990 was tasked with developing and coordinating “a comprehensive and integrated United States research program which assists the Nation and the world to understand, assess, predict, and respond to human-induced and natural processes of global change.”
You can order your copies from GlobalChange.gov.
The report clearly explains the indicators that indeed our planet is heating up. Some of these indicators show an upward trend, while others show decreasing trends. Let’s take a look at two of those upward trends, surface temperatures and heavy precipitation, since they are currently in the news.
Indicator – Heat Waves
As I write this, much of Europe is experiencing the hottest temperatures ever recorded. France reached nearly 115 °F. According to the National Aeronautics and Space Administration Goddard Institute for Space Studies’ surface temperature analysis, 18 of the 19 hottest years have occurred since 2001. As you can see by this graph, it is likely that upward trend will continue until we take drastic measures.
According to the World Health Organization, “Extreme high air temperatures contribute directly to deaths from cardiovascular and respiratory disease, particularly among elderly people. In the heat wave of summer 2003 in Europe for example, more than 70,000 excess deaths were recorded.”
Indicator – Heavy Precipitation
Our water cycle is simple. Water is evaporated from the surface of the earth, either from the ocean, other bodies of water, or the ground, and is then converted into clouds and fall as precipitation, which returns to the sea. The amount of water the air can hold depends on how warm the air is, and our air is warming as you saw above. Our oceans are also warming. According to Center for Climate and Energy Solutions, for each 1 °F of warming, the air’s holding capacity for water vapor goes up almost 4%. This results in bigger, extreme downpours.
Just ask those living in the Midwest. Their lifestyles are disrupted, as well as the supply of crops they produce.
In the US these extreme downpours are happening 30% more often, and are 10% more intense. Hurricanes become more intense much more quickly due to warmer oceans. Since our atmospheric air is warming, it is holding more water and releases a lot more water as a result.
Another indicator is a wavier jet-stream. This means our air currents are dipping much deeper than they did before. This brings down colder air from the arctic into regions such as the Midwest, and pushes up warmer air from the south into the arctic. This pattern also holds pressure systems longer, causing longer periods of rain, drought, hot or cold, depending where you are in the system.
Because of rising sea levels from the melting of arctic ice, we are seeing sunny day flooding in cities such as Miami and other southern U.S. communities.
When Hurricane Harvey passed over Nederland, Texas, it released 5 feet of rain. That is equivalent to the flow of Niagara Falls for 500 days. Can you even imagine that amount of water?
Hundreds of families were displaced and many losing their family homes.
These are just two of the indicators that our climate is changing. Others include higher numbers and more intense wildfires, ocean acidity, longer growing seasons, and drought conditions. Decreasing trends include reduction in sea ice and western snow-pack.
I recommend reading the executive summary of the Fourth National Climate Assessment so you can make informed decisions. And as always, remember that every purchase and action you take affects everyone else on this planet.
In future articles I will share good stories of wonderful people doing amazing things. There is hope, but it takes all of us to make the changes we need to stop these trends.