J.C. Moore Online

Current Events from a Science Perspective

Science is about using observation and reason to understand the physical world. Some people are suspicious of computer models and theories; so here is the basic data about global warming in pictures and graphs.

Ice Ages: In the past, the Earth’s temperature has varied from the Ice Ages to the much warmer temperatures of the interglacial periods.  Ice core data gives a good picture of what has happened to the Earth’s temperature in the last half million years, as shown by the blue line. The changing temperatures are attributed to the Milankovitch Cycles, small variations in the Earth’s orbit that cause the Earth to receive different amounts of sunlight. The Earth becomes slowly warmer during the periods where the solar energy increases. As the Earth begins to be warmed by sunlight, CO2 becomes less soluble in the ocean and the CO2 concentration in the atmosphere increases, which further amplifies the warming since CO2 is a greenhouse gas.

As you can see in the graph, the red line shows how intricately the CO2 concentrations and temperatures are related. The CO2 concentration drops to about 180 ppm during the glacial periods and rises to about 290 ppm during the warmer interglacial periods. As the far right of the graph shows, we are now in an interglacial period that began about 6000 years ago. The Milankovitch Cycles predict that Earth should slowly cool for the next 20,000 years, but it is warming instead.  Please note that the concentration of CO2 did not rise above 300 ppm in any previous warmer periods but on the far right side of the graph, the red line indicating the CO2 concentration is now approaching 380 ppm. http://www.daviesand.com/Choices/Precautionary_Planning/New_Data/IceCores1.gif

Current CO2 Levels: In the past, the warming oceans released the CO2 as a natural process. However, man is now putting about 30 billion tons of carbon dioxide into the air each year. Much of it stays there and the Keeling curve below shows how CO2 is building up in air. What might that mean for man? In 2011, the CO2 concentration reached 387 ppm, far higher than it has been for perhaps 15 million  years.

 This article explains what the Earth may have been like then: “The last time carbon dioxide levels were apparently as high as they are today — global temperatures were 5 to 10 degrees Fahrenheit higher , the sea level was approximately 75 to 120 feet higher, there was no permanent sea ice cap in the Arctic, and very little ice on Antarctica and Greenland.”

Earth’s Temperature: Carbon dioxide is one of the greenhouse gases that warm the Earth. NASA’s graph below shows how its increase is changing the Earth’s temperature. Though the Earth’s mean temperature varies widely from year to year, the graph on the right is a moving average that allows you to see the trend in the temperature much easier.

                                                           htp//data.giss.nasa.gov/gistemp/2010november/fig2.gif

  The effect of particulates, which cool the Earth, can be seen around 1991 when Mount Pinaturbo exploded. The flat place in the graph from about 1940 to 1970 is attributed to particulates generated by World War II, atmospheric atomic bomb testing, and postwar industrialization – before particulate emissions were regulated. Clearly, the Earth is getting warmer.

Record Temperatures: Nine of the 10 hottest years on record occurred in the last decade. The other record-breaking year was 1998. the chart gives the record temperatures for 50 years and the inset for the last last 160 years.

This has led to extreme heat waves  in areas such as Moscow.

Effect on the Weather:  According to NOAA, global warming is affecting the El Niño and La Niña ocean currents cycles which affect  the weather patterns in North America.  The cycles are occurring at higher temperatures and are becoming more unpredictable . Changes in ocean currents may be a major tipping point in climate change.

Effect on the Earth: Scientist tell us that the increasing CO2 concentration is leading to a warmer Earth, more extreme weather, melting glaciers and polar ice, crop failure, droughts, and wildfires. We have certainly experienced many of those things recently, which should make us think about what effect our activities are having on the Earth. Many of the changes in the Earth are subtle, but here are two of NASA’s pictures that clearly show how the Earth is changing. Between 1979 and 2010, about 30% of the Arctic ice has disappeared.

 This has greatly affected the way of life of the native Inuit who live and hunt on the Polar ice.  While they may adapt, their way of life and culture which sustained them for centuries will be destroyed. The Polar bears, uniquely adapted to live in on the Polar ice, have been put on the threatened species list because their habitat is clearly declining.  As their habitat disappears, so will be the Polar bear. It is something man should think about – as our habitat is deteriorating, also.

 Note: This was posted on 09/01/2011 and updated on 03/06/2013 to include data that was not presented in this more comprehensive collection of pictures and graphs of global warming data.

(c) 2011/ 2013 J.C. Moore

“Pictures of the polar region from 1979 and 2003 clearly show that about 30% of the Arctic  ice has melted. This has greatly affected the way of life of the native Inuit who live and hunt on the Polar ice.  While some may adapt, their way of life and culture, which sustained them for centuries, will be destroyed.”

Although arguments still rage about whether the Arctic sea ice is disappearing, the disappearance is a fact of life for those who live near the Arctic Ocean.   The photos clearly show that the Arctic Sea ice is disappearing. A recent TulsaWorld article described how the disappearance of the Arctic sea ice has affected the lives of the native Inuit people in Greenland. Ice which used to be 2 meters thick in the winter, now grows only a few centimeters thick, far too thin to allow dogsleds to go to the nearest town, 50 miles away across the bay. They can no longer venture onto the ice to hunt for seals or walrus, a mainstay of their diet,  nor can they go out on the ice to fish. The Polar bears they sometimes hunt have no fat, as the bears cannot swim to the ice packs to hunt, and they sometimes prowl the villages looking for food.

Drilling for oil has picked up in the area as the ices disappears, but so far little oil has been found. Exploration continues, and if oil is eventually found, it carries the possibility of  economic development. But it also carries  the possibility that an oil spill, almost impossible to clean up in the icy  environment, would destroy much of the ocean life the natives now depend on for food. The sad thing is that they are being forced to change a way of life that sustained them for centuries. While some may adapt, their way of life and culture will be destroyed, and many will likely end up among the poor and unemployed.

Note added on 03/22/ 2018: A recent article from the American Geophysical Union Journal EOS highlights the health risks to native Alaskans and describes the plight of the Inuit from climate change. Here are the words of one of their elders:

” Charles Sollie Hugo, a Native elder and oral historian with the North Slope Borough in Barrow, grew up hunting with his family. However, as the times when rivers freeze has shifted to later in the fall and their thawing has begun earlier in the spring, the window of time when it’s safe to traverse the land has narrowed, making caribou hunting less of a part of his life, he said.

Traditional permafrost cellars that Hugo once used to preserve meat have thawed, flooded, and become inaccessible.Traditional permafrost cellars that Hugo once used to preserve meat have thawed, flooded, and become inaccessible. “They are full of water right to the top,” he said. “They are no longer usable. They are contaminated because the permafrost is thawing out.”

(c) 2011 J.C. Moore

Global warming may not have much effect on those in the U.S. Midwest, but others may find it very difficult to “Just adjust”.

Redbud that thinks it's Spring.

Pears that have not seen frost by Thanksgiving.

These are not great pictures, but I was not planning to write an article when I took them the day before Thanksgiving this year. But, they have a message. One shows our redbud tree that budded into green leaves as if it were Spring after going dormant for the year. The pear tree still had pears and green leaves not yet bitten by frost. They reminded me of my family’s Thanksgiving photo taken in front of my dad’s apple tree in1998. We were all in shirtsleeves and the apple tree still had green leaves, as it had not yet frosted that year. My father, then 88, said that never in his memory had a frost been so late. It turned out that 1998 was one of the hottest years on record but this year may set a new record. It is interesting that two of the latest frosts in our area in almost a century have occurred after Thanksgiving – and in the past 12 years.

Other subtle changes have taken place in my lifetime. We used to be in gardening zone six but we are now in zone seven. That means we are now having warmer winters, later frosts, and earlier warm-ups in the spring. Several times our fruit trees bloomed during a false spring in February only to have the blossoms nipped by a later freeze. We have a longer growing season which sounds good. That also means a longer season for insects and pests and they have shown up in greater abundance. Our gardening is a hobby so it is not a serious matter if we lose a crop to early freezes or pests. We recently have had record rainfall in the spring and three years ago the ground was wet for so long it drowned some of our fruit trees. But, we are now experiencing dryer weather in late summer and early fall – and the redbud tree in the picture had its leaves turn brown by September from dry weather. Scientists cannot predict the weather but only that the warming Earth will cause weather to become more extreme – and we seem to be observing that.

The signs of a warming Earth are sometimes subtle and it is rather hard to tell if that is the cause of changes we see. Biologists are telling us that some species are extending their range to the North. We now have fire ants and armadillos which were not around when I was growing up. I recently found some Kudzu growing over at the lake and some along a fence near my house. Kudzu is an invasive plant that chokes out other vegetation and kills trees; it thrives in higher CO2 levels and warmer temperatures. I certainly hope it doesn’t get started here. And sadly, the quail which were plentiful during my childhood have disappeared from the hills and fields in this area. Some say foraging armadillos are responsible by destroying their nests, but no one really knows for sure. I’m not sure the quail’s disappearance had anything to do with global warming but they have come to symbolize for me that subtle changes are taking place. It’s sad that good things may change and my grandchildren may never be aware of the things that are gone.

There is sound scientific evidence that the Earth is warming and those who long denied the evidence have now shifted their message, saying we should “just adjust”. I’m not sure what that means, but those of us who live in the Midwestern United States will probably be able to do so. It may be more difficult for other people in the world. The people of Kashmir are concerned that the glaciers that feed their streams in the summer are receding – making less water available. The Sherpa of Tibet are worried that their villages may be flooded by lakes that now form each summer from melting glaciers . The lakes are held back by ice dams and, if a dam breaks, it will be a catastrophe for their villages. The Inuit in the Arctic are having to move their coastal villages to keep them from being eroded away by wave action of open seas which were year round ice before. Their inland villages are threatened as well as the permafrost upon which some were built now becomes a quagmire in the summer. Telling the people whose lives will be changed forever by global warming to “just adjust” seems a little hollow.

(C) 2010 J.C. moore

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