Are you one of the three people still influenced by the two remaining politicians being paid by Big Oil to deny Global Warming exists? NEWS FLASH: Human-Burned Fossil Fuels are the Major Culprit Killing the Planet as we Know It.
Climate change has crept upon us and the consequences are manifest around the globe. Heat waves are becoming more frequent while the incidence of record-low temperatures and cold snaps is on the decline. In regions such as the Sierra Nevada mountain range of the United States, there has been a documented drop in average snowfall and snowpack. Since warmer air has more water vapor, climate change has also altered the pattern of precipitation. In the United States, for instance, precipitation has intensified, increasing by about 5% over the last 5 decades.
Warming is particularly striking in the Arctic region where the extent of sea ice has continued to drop by approximately 10% per decade since the late 1970s. In the late summer, shockingly large areas of the Arctic Ocean are devoid of ice for long periods, raising concerns about adverse effects on ecosystems, national defense, and shipping routes. The high temperatures have also warmed the ocean waters, and since water expands at higher temperatures, sea-levels have risen by about 0.2 m or 8 inches. Additionally, glaciers and ice sheets in various other locations around the world are rapidly melting with the excess water adding to the rising sea levels.
The warmer climate has also had a significant impact on flora and fauna. Many species of plants and animals are now being found at higher altitudes where the temperature is lower. The timing of various seasonal events is also changing. For example, animals and insects are migrating earlier, and breeding patterns are being altered.
With the development of advanced data collection systems such as satellite monitoring and powerful computerized simulation models, climate science has become more precise. We now have overwhelming evidence in the form of measurable data to support the phenomenon of global warming and climate change. Importantly, we also have data that implicates human activities as the major catalyst in the process.
The Earth’s surface temperature has been measured for over a century and there is incontrovertible proof that we are now living in a hotter world. Modern thermometers are located in thousands of positions over land and oceans, and the raw data is collected by specialized research groups such as the NASA Goddard Institute for Space Studies in the United States. The analyses of the temperature data have demonstrated an average increase in the Earth’s surface temperature of over 1.4oF or 0.8oC over the last three decades. To put things into perspective, the difference between the global average temperatures of an ice age and the climate today is estimated to be a mere 9oF!
The temperature of the Earth’s surface is only one of several components of the global climate system monitored today. Specialized equipment is used to track ocean conditions such as salinity, temperature, and currents while weather balloons track atmospheric temperature, winds, and humidity. Additionally, remote satellite sensors provide a global perspective of atmospheric and surface changes in the climate system. While the data sets from these various sources are obtained in vastly different ways, they all consistently indicate that the earth is rapidly warming.
At the dawn of the 19th century, scientists began to realize the regulatory role of certain gases in maintaining the temperature of the Earth. These greenhouse gases, which include carbon dioxide and methane, form an insulating blanket around the earth and are crucial to its habitability. As the Sun’s energy warms the Earth, the blanket of greenhouse gases prevents the radiated infrared energy from escaping the atmosphere, keeping the surface from freezing. Unfortunately, the greenhouse effect is amplified with rising concentrations of greenhouse gases.
Human activities generate massive amounts of greenhouse gases and most scientists agree that we are largely to blame for the warming of the Earth. Methane is produced from the burning of fossil fuels, the raising of livestock, and from landfills. Carbon dioxide is also released from burning fossil fuels, while activities like deforestation reduce the rate at which it is removed from the atmosphere. Nitrous oxide results from use of fertilizers. CFCs are greenhouse gases that do not occur naturally, and their presence in the atmosphere is undoubtedly a result of human activities.
There is another line of investigation that implicates human activities in the amplification of the greenhouse effect. The study of air bubbles trapped in polar ice cores has shown that the concentration of CO2 in the atmosphere was steady for at least 2,000 years prior to the Industrial Revolution. Towards the end of the 19th century, atmospheric C02 spiked sharply and has been trending upwards ever since. The concentration of CO2 in the atmosphere today is 40% higher than preindustrial levels, bringing it to its highest point in the past 800,000 years.
In addition to direct and indirect measurements of C02 concentrations, scientists have estimated the amount of CO2 that is naturally absorbed by the Earth’s land and oceans. They have also consolidated data on the amount of fossil fuels burned each year. The analyses indicate that at least 45% of the C02 produced from human activities is retained in the atmosphere. Carbon fingerprinting technology identifies fossil fuels as a major source of the carbon found in this greenhouse gas, providing further evidence that humans are culpable in climate change.
Scientists have also explored alternative explanations for climate change. Since the Sun has an obvious impact on the Earth’s temperature, solar activity has been analysed meticulously. Satellite records show the Sun’s output to have remained constant in the past 30 years. Indirect methods before the satellite era have similarly indicated that the sun’s activity could not have been responsible for any temperature increases beyond the latter 20th century. Finally, weather balloons show cooling of the higher stratosphere with warming of the lower troposphere. This observation is consistent with the theory that rather than the atmosphere being warmed from the sun above, heat is being trapped closer to the earth.
The Damage. Plain and Simple.
The energy landscape of the future will have a pivotal role in the progression of global warming. Taking into account variables such as population growth, technological developments, land use, and global energy-conservation policies, we can project changes in the average temperature of the earth by extrapolating trends in greenhouse gas production. To achieve this, scientists use powerful climate models built around mathematical equations that represent the dynamics of the climate system. In 2005, the World Climate Research Programme integrated the findings of 23 such modelling experiments from around the globe to predict climate changes. These experiments were based on three different scenarios of greenhouse gas emissions – high, medium-high, and low. All three emission levels predicted continued warming, with the scenario of the highest emissions leading to a greater than 110F rise in global temperature.
Results of another, independent study showing scenario A2, business as usual, resulting in more than 7 degrees warming.
Extreme Heat and Fluctuation
A climate change of this magnitude will lead to a spectrum of societal and ecological problems. First off, as the trend of global warming continues, it is obvious that various regions of the globe will suffer from higher average temperatures. The heat index, which combines humidity with temperature to give a value for how hot it feels, is predicted to increase throughout this century. By the year 2100, Central USA alone is expected to experience about 90 additional days each year of heat indexes higher than 1000F. Additionally, heat waves will become more intense, with the inference that heat-related morbidities will also rise. Overall, the ratio of record high to record low temperatures is projected to rise from the current 2:1 to 50:1 within the span of a handful of decades.
Global warming will also have a significant impact on precipitation. As the world becomes hotter, the existing regional contrasts in rain and snow fall will become more pronounced. While polar and sub-polar regions will likely see greater snow and rain, many other areas will become dryer. In fact, for each 1.80F rise in temperature, the world’s deserts will see a 10% reduction in precipitation, worsening the impact of droughts. In countries such as the USA and Canada, the ultimate effect of global warming on precipitation is still uncertain. However, most climate models predict a dryer future for the southwest regions of the United States.
Along with disturbing the pattern of precipitation, global warming will also lead to greater incidences of extreme weather. Heavy rainstorms are already becoming more frequent globally and simulation models project a continuation of this trend. For each rise of 1.80 F, we can expect extreme rainfalls to intensify by 10%. In contrast, dryer regions will experience harsher droughts, making fire-prone areas more vulnerable to wildfires. As an example, the northern Rocky Mountain forests of the United States are predicted to experience a doubling in fire damage for each 1.80F rise in global average temperature.
Less Snow, Aquifer-Based Water, River Water, Hydro-Power
Another effect of global warming that is already starkly obvious is the decline in snow and ice cover over land and ocean. In the future, the sea-ice cover during the month of September is expected to diminish by a drastic 25% per 1.80F rise in temperature. As matters currently stand, the Arctic Ocean is expected to be seasonally ice-free before the end of this century. Terrestrial snow cover will also continue to diminish, with snow pack building later and melting earlier in the season. This will adversely affect not only the availability of fresh water, but also the ability to generate hydroelectric power.
Shore Line Erosion
As global temperatures rise, ocean water will continue to expand as it becomes warmer. In 1990, climate models predicted rises in sea-level for various scenarios of global warming– we are already near the top of the range of projections. The thermal expansion of oceans is by no means over, and its effect on sea-level is only being exacerbated by the melting of glaciers and sea-ice.
In Alaska, coastal erosions have already forced thousands to relocate. With the sea-level expected to rise another meter by the turn of the century, further loss of coastlines is imminent. If the sea-level rises by 0.5 meters, it is estimated that over 250,000 sq. km of land could be flooded worldwide, permanently displacing about 4 million people. At a rise of 1 m, coastline losses would be much more profound. In the US, for instance, over 90% of New Orleans, and 18% of Miami would be susceptible to flooding.
Ecosystems are also under constant threat from global warming, with cold-adapted species being particularly vulnerable to changes in temperature. As lower altitudes become too warm for habitation, animals like the American pika are being confined to the cooler mountaintops. Such shifts in habitation of terrestrial organisms have disrupted important life-cycle events such as blooming, pollination, and hatching, wreaking havoc on food webs and inter-species interactions. In the ocean, it is feared that warmer temperatures will lead to loss of phytoplankton, an organism crucial to the ocean food web.
Last but not least, a significant impact of global warming will be on food security worldwide. As C02 levels rise in the atmosphere, there is an intuitive expectation for crops and foliage to prosper. In reality, while plants do grow faster with higher concentrations of available C02, the rapid growth means there is a shorter period during which grain is available. Furthermore, the higher temperature that results from increased atmospheric CO2 places greater water stress on crops, increasing risk of damage.
In the USA, half the country’s produce is grown in California. By 2050, it is projected that global warming will decrease yields of a variety of nuts and fruits by as much as 40%. Similarly, for each 1.80F of warming, the corn yield in the US and Africa will decline by 15%. At 90F of warming, yield losses would be global, doubling the price of grain worldwide.
There’s more. There are reams and reams of data that tell us we’re killing the planet as we know it. We can predict certain death and destruction to plants and animals, to the shoreline we’re familiar with, to entire ecosystems and species.
We (humans collectively) don’t know if we’re too late. Have we reached a tipping point – that point at which there is no relief from the high emission concentrations but the slow demise of humans, perhaps dwindling our numbers to the point we can no longer damage the planet?
Most scientists agree we can make a difference. If we act now – all of us on the same page saying no to the special interests that would have us keep burning oil and lining their pockets with cash.
The next article goes into some detail about ways we can mitigate and even reverse our folly. Read on. Hope is a terrific thing to have. Political clout as we all ban together is an absolute requirement to Save our Ship. Spaceship Earth.
- NASA: Global Climate Change, Vital Signs of the Planet http://climate.nasa.gov/evidence
- Belolipetsky P.V., Empirical evidence for a double step climate change in twentieth century, 2013, arXiv:1303.1581 [physics.ao-ph]
- National Research Council, 2010, Advancing the Science, Limiting the Magnitude, and Adapting to the Impacts of Climate Change
- National Research Council, 2010e, Ocean Acidification: A National Strategy to Meet the Challenges of a Changing Ocean
- Hansen, James, Makiko Sato, and Reto Ruedy. “Perceptions of climate change: The new climate dice.” Procedings of the National Academy of Science 119 (2012): 14726-14727.