n a recent essay (XIV) we looked at the effects of global warming on glaciers and ice sheets and the resulting effect on ocean levels and coastal cities. Now let’s broaden our scope and include the ripple effect of climate warming on the inhabitants of not only frigid climates but also warmer areas as well. First, let’s look at polar bear population changes and the reasons for their decline.
From cartoons to Coca-Cola commercials to zoos, no animal is quite as majestic as those beautiful lumbering polar bears. These massive animals, the largest of the Ursines may accomplish what years of environmental activism hasn’t done: convince people that global warming is real and happening now. This “puts a face upon it, a polar bear face” according to Bob Corell, director of the global change program at the Heinz center for Science, Economics, and the Environment. But it may be too late for the 25,000 polar bears that inhabit the wild from Alaska to Greenland. There’s so much climate change inertia built into the system already” he says. (rrrstar, May 18, 2008) Polar bears depend on’ sea ice for hunting seals, which is their favorite food. They rarely catch seals on land or in water and if they do they usually expend a lot of energy (rrstar September 8, 2007 as the following example illustrates. Some polar bears in the arctic are shedding pounds at a time when they should be gaining weight Scientists blame global warming for the shrinking ice cover on the Arctic Ocean. Scientists attached tracking collars to nine female bears (males tend to shed the collars from their narrower necks and smaller heads) in a recent study. Also equipped with video cameras, everything they saw the researchers saw too. They periodically were weighed and had their blood monitored for ten days. Five bears lost weight and four of them lost 2.9 to 5.5 pounds per day. One bear lost 51 pounds in nine days in April when they would later be raising cubs. But because the ice is shrinking they were having a harder time catching seals. With less ice, which is also broken up, they have to travel farther and at times swim to catch their prey which increases the risk of hypothermia and expends more energy just when they need more reserve. Some of the bears traveled more than 155 miles in 10 days along the northern coast of Alaska in the Beaufort Sea. The average bear burned 13,200 calories a day-six times more than an active human female. As stated in an earlier essay the ice cover grows in winter and shrinks in summer but in the last several years the shrinking is far greater than the growth (rrstar February/2, 2018.).
However, some scientists believe that if the world dramatically changed its increasing emission of greenhouse gases, a total loss of summer sea ice could be averted
Let’s now turn our attention to a much different aquatic environment–to tropical waters and the effect of ocean warming on coral reefs. Coral are beautiful animals (even though they look like plants) of the phylum Cnidaria, (formerly Coelenterata) that live within stone-like “tubes” that build up into the familiar reefs. These reefs provide food and shelter for countless varieties of
sea creatures. Many corals have a mutualistic symbiotic relationship with algae in which the algae make food (photosynthesis) for the coral and the coral provide a home for the algae. Coral reefs form the basis for a multibillion-dollar tourism and commercial fishing economy in tropical marine areas around the globe. Reefs also limit damage from hurricanes and tsunamis. They also have recently been shown to be possible sources for new medicines.
However, bleaching of the coral from record hot water has made world headlines over the last several years. Bleaching occurs when the heated water kills the algae thereby causing loss of color. If coral remains bleached for more than a week, the odds for death increases significantly. Bleached coral are more susceptible to disease. Recently a chunk of brain coral 3 feet in diameter was found that was about 90 percent dead (rrstar November 12, 2017) near St. Thomas in the Caribbean. Zooxanthellae, commonly called “gooks” is the algae found in coral. (Gore, A 2006)
Let’s examine the effects of human activities on a terrestrial ecosystem, or more correctly, biome–tropical rainforests. From the editors of the Environmental Magazine in the Belvidere Daily Republican October, 2009), 80, 000 acres of tropical rainforests are being lost daily and an equal amount are being degraded.
Rainforests are extraordinarily rich in nutrients and biodiversity. They help maintain climate by sequestering carbon dioxide and are home to perhaps 50 percent of the world’s species. Twenty five percent of our pharmaceuticals are derived from rainforest ingredients. Why are rainforests being destroyed? Mainly they have fallen (literally) to logging, farming crops and cattle ranching) but also to dam- building and mining.
Let’s consider the effects of climate change on weather patterns such as storms, including hurricanes, tornadoes, and snowstorms from the viewpoint of their frequency and intensity. In February, 210, Washington D. C. received over two feet of snow followed by a six day cold spell. Undoubtedly many peoples were saying “where is global warming now?” That doesn’t refute a trend of
rising global temperatures. At the same time snow had to be trucked in to Vancouver, British Columbia, so that the winter Olympics could go on as scheduled. A one- time weather event is still a one-time weather event. (Belvidere Daily Republican February 25, 2010). Also from the Belvidere Daily Republican issue of September 22, 2005, scientists state that warmer ocean temperatures in the tropics between June and November cause instability
in the lower atmosphere which then ‘fuels” developing hurricanes. Following that line of reasoning, it followers that even further warming temperatures will add more strength. The data seems to back that up. Tropical storms in both the Atlantic and Pacific Oceans have increased in duration and intensity by 50 percent since the 19770’sThe hottest years in recorded history up to the date the article was written were the years 1990-2004 which coincided with the greatest worldwide emissions of CO2. That the intensity of hurricanes has increased is borne out by that fact that there was an average of about 11 Category 4, or 5 storms per year in the 1970’s compared to an annual average of 18 in the 1990’s. This increase coincides with a nearly one degree Fahrenheit sea temperature rise. Warmer ocean temperatures increases the water vapor content of the atmosphere resulting from greater evaporation and cloud formation. Remember from essay IV (hydrologic cycle) that water vapor can also be a greenhouse gas since clouds help trap heat. At least one meteorologist questioned the above data saying that wind speed estimates of storms in the 1970’s were based on older technology they may not have been as accurate. However, another scientist countered that increases have been steady over the years. “It didn’t just kick in when the new technology measurement methods kicked in” (rrstar, September 18, 2005).
References
Rockford Register Star (May 18, 2008) “Polar bear’s impact on people is felt”
Rockford Register Star (September 8. 2007) Report: Massive polar bear deaths predicted”
Rockford Register Star (February 2, 2018) Climate change diet: As ice thins, so do polar bears”
Rockford Register Star (November 12, 2017) “Caribbean coral suffers record bleaching death”
Belvidere Daily Republican (February 25, 2010) “Strange snow patterns are consistent with climate change”
Belvidere Daily Republican (September 22, 2005) “Earth Talk: Does global warming affect tropical storms?”
Rockford Register Star (September 18, 2005) “Study: More hur4icanes growing to strongest categories”
