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EXAMPLES OF ARTICLES WHICH CONTAIN MODALS


Global Warming

Reason for Alarm?


BY GABRIEL N. LISCHAK
JULY 10, 2006
REAL TRUTH MAGAZINE

According to some, humanity is sitting on a volatile time bomb—one that could send the entire planet into a tailspin of epic destruction, with detonation not far in the future. But is this a realistic scenario?
The facts are in: The thermohaline ocean current—which moderates temperatures worldwide, preventing Europe from having a climate similar to Alaska—is slowing. Glaciers in Greenland, Alaska, the Himalayas and the Antarctic Peninsula are retreating. Sea ice in the Arctic Ocean during summer is disappearing. Permafrost (permanently frozen soil) in Canada, Alaska and Siberia is melting at an alarming rate. Hurricanes are becoming more numerous and more intense, and sea levels are rising.
According to the National Academy of Sciences, the average surface temperature of the earth has risen by one degree Fahrenheit (°F) during the past 100 years, with accelerated warming occurring within the past 20 years. NASA climatologists state that 2005 was the warmest year in a century, with 1998, 2002, 2003 and 2004 next in line. 
Few dispute that the earth is growing warmer and that there are signs identifying this. The debate lies in the seriousness of this warming trend, who or what is to blame, and whether there is a direct connection to hurricane frequency and intensity.
The term “global warming” is at the forefront of many minds, and for several reasons. Should we be concerned?

Greenhouse Gases

The earth’s climate and weather is driven by energy from the sun. This energy heats the planet, which in turn radiates that heat back into space. However, much of this heat is retained by various greenhouse gases in our atmosphere, such as carbon dioxide (CO2), methane and nitrous oxide—and this is a good thing. Without such gases contributing to this natural greenhouse effect, life as we know it would not exist. Temperatures would be similar to our airless moon, ranging wildly from 225°F during the day to negative 243°F at night. Obviously, this would not be an environment conducive for life. But due to greenhouse gases, the earth’s average temperature is a hospitable 60°F. However, problems arise when the concentration of these gases increase.
Huge amounts of carbon have been captured by plants and buried in the ground in the form of coal, oil and natural gas, called fossil fuels. (In contrast to human beings, plants take in CO2 and expel oxygen.) These fuels have accumulated over the course of perhaps millions of years. With the advent of the Industrial Revolution, mankind began extracting and burning earth’s vast reservoirs of these fuels. This released millions of tons of carbon, in the form of CO2, into the atmosphere, thus increasing the levels of greenhouse gases beyond what the earth can safely handle. Since then, atmospheric concentrations of CO2 have increased nearly 30%, methane concentrations have more than doubled, and nitrous oxide concentrations have risen roughly 15%. These increases have enhanced the heat-trapping capability of earth’s atmosphere, and will continue to do so for years to come.
Fossil fuels burned to power cars and trucks, heat homes and businesses, and power factories are responsible for about 98% of U.S. CO2 emissions, 24% of methane emissions and 18% of nitrous oxide emissions.
http://realtruth.org/images/polar_bear-asha-090316.jpg 
At risk: On the frozen Beaufort Sea outside the Inupiat village of Kaktovik, Alaska, a polar bear pauses from a meal of whale meat. The 3,800 polar bears along the Alaskan coast face an uncertain future as global warming melts more summer sea ice each year.
Source: KRT
Also contributing a significant share of emissions are increased agriculture, deforestation, landfills, industrial production and mining. In 1997, the United States discharged roughly one-fifth of the world’s total greenhouse gases.
Estimating how much of these gases will be emitted in the future is difficult,(1) as it depends on demographic, economic, technological, policy and institutional developments. Based on differing projections of these principal factors, several scenarios have been developed.
For example, in the absence of emissions control policies, by the year 2100, CO2 concentrations are projected to be 30 to 150% higher than today’s levels. However, even if human beings were to cease emitting heat-trapping gases into the atmosphere, (2) the climate still would not stabilize for quite some time, as the gases that are already there will remain for decades, even centuries.

Future Warming Uncertain

It is not easy to decipher to what extent this human-induced accumulation of greenhouse gases is responsible for the global warming trend. Other factors—natural climatic variations, changes in the sun’s energy, and the cooling effects of pollutant aerosols—affect our planet’s temperature, and understanding in these areas is incomplete.
Nevertheless, the Intergovernmental Panel on Climate Change (IPCC) stated there is a “discernible” human influence on climate. The observed warming trend is “unlikely to be entirely natural in origin.” In another report, the IPCC wrote, “There is new and stronger evidence that most of the warming observed over the last 50 years is attributable to human activities” (U.S. Environmental Protection Agency).
While scientists estimate that average global temperatures will continue to increase as levels of greenhouse gases rise, how much and how quickly remains uncertain. The IPCC projects that the planet will warm by an additional 2.2 to 10°F in the next 100 years. This large range is due to various uncertainties, such as future greenhouse gas emission rates, the possible cooling effects of atmospheric particles such as sulfates, and the climate’s response to changes in the atmosphere.
Even the low end of this warming projection “would probably be greater than any seen in the last 10,000 years,(3) but the actual annual to decadal changes would include considerable natural variability” (ibid.).
The computer models used to forecast global climate change are still unable to accurately simulate how things may change at smaller scales.(4) As a result, scientists generally feel more certain about large-scale projections (global temperature and precipitation change, average sea level rise) than small-scale ones (local temperature and precipitation changes, altered weather patterns, soil moisture changes).
As with perhaps all fields of scientific study, uncertainties associated with the science of global warming exist. Some aspects of this science are based on well-known laws and documented trends, while others range from “near certainty” to “big unknowns.”

Melting Ice

The Arctic, one of the most forbidding environments in the world, is home to the polar bear. During the summer, these animals roam this region on large chunks of floating ice, drifting for hundreds of miles. This is how they find mates and hunt for seals, fattening themselves to prepare for the severe winter. If these palettes of ice did not exist, the polar bear would not survive.
Within the past three decades, more than one million square miles of sea ice—an area the size of Norway, Denmark and Sweden combined—has vanished. Presently, ice at the southern Arctic region of the polar bear’s range is melting about three weeks sooner than has previously been the case. This affords the bears less time to hunt, eat and store fat. Due to this early melting, the Hudson Bay polar bear population has declined by 14% during the past ten years.
Some climate models predict that 50 to 60% of this vital summer sea ice will disappear by the end of this century; others predict that by just 2070, the Arctic will be completely ice-free in the summer. (5) If this does indeed occur, the world’s largest bear could become extinct.
Meanwhile, glaciers in Greenland are receding at alarming rates. Within the last five years, those along the eastern and western coasts have receded about 300 miles each. Although a total meltdown is highly unlikely, with more than one-fifth of the population living less than two feet above sea level, not much melting is required to cause significant damage.
Permafrost in the Arctic region is diminishing as well. According to a report in the Geophysical Research Letters, it could shrink by 60 to 90% by 2100. A National Oceanic and Atmospheric Administration climate scientist states that this will increase freshwater runoff into the Arctic Ocean by 28%, lead to the release of large quantities of greenhouse gases from the soil, and upset ecosystems within a wide area.

Hurricanes Increasing?

The year 2005 was a record-breaking one for Atlantic hurricanes, with the most named storms, the most hurricanes and the most Category-five hurricanes occurring—with New Orleans and the Mississippi Gulf Coast being nearly destroyed by Hurricane Katrina. In terms of barometric pressure, the Atlantic Basin also experienced its most intense hurricane ever that year, Hurricane Wilma.
Some studies reveal that tropical storms around the world are intensifying, with computer models suggesting a shift toward extreme intensity. A big question on many minds is, “Does the warming of the earth have a direct effect on the strength of hurricanes?” Opinions are varied.
Scientists caution that one must consider questions of climate change over decades, (6) even centuries. A particularly rough hurricane season or two cannot be blamed on global warming. (7)
Preliminary evidence suggests that, once hurricanes form, they will be stronger if the oceans are warmer. (8) However, much uncertainty exists about whether hurricanes and other storms will become more frequent.
According to the Geophysical Fluid Dynamics Laboratory, which assesses natural climate variability, “The strongest hurricanes in the present climate may be upstaged by even more intense hurricanes over the next century as the earth’s climate is warmed by increasing levels of greenhouse gases in the atmosphere. (9) Although we cannot say at present whether more or fewer hurricanes will occur in the future with global warming, the hurricanes that do occur near the end of the 21st century are expected to be stronger and have significantly more intense rainfall than under present day climate conditions.” This is based upon an anticipated increase of energy from higher sea surface temperatures.
A study published in the Journal of Climate indicates that an 80-year buildup of atmospheric CO2 at 1% per year (compounded) leads to roughly a one-half category increase in potential hurricane intensity on the Saffir-Simpson scale, and an 18% increase in precipitation near the hurricane’s core. Of course, if emissions of CO2, along with other greenhouse gases, were to be higher, then hurricanes could potentially become even stronger.
However, many other scientists are quick to point out that since the 1940s, there has been an overall decrease in hurricane activity. According to the United Nations Environment Program of the World Meteorological Organization, “Reliable data…since the 1940s indicate that the peak strength of the strongest hurricanes has not changed, and the mean maximum intensity of all hurricanes has decreased” (CNSNews).
In September 2004, in response to some labeling the busy hurricane season a byproduct of global warming, a group of climatologists, scientists, professors and other experts in climate change stated, “Computer simulations suggest that in a warmer world most of the warming would occur in the Polar Regions. Atmospheric circulation, which crucially affects storms, is driven primarily by the temperature difference, or gradient, between the tropics and the poles.
“Warmer polar regions would reduce this gradient and thus lessen the overall intensity or frequency or both of storms—not just tropical storms but mid-latitude winter storms as well (such as blizzards and northeasters).
“Again, longer periods of history bear this out. In the past, warmer periods have seen a decline in the number and severity of storms. This is well-documented in scientific journals for data extending back centuries or even millennia. If the surface temperature of the planet rises further in the future, it is likely that these declines will continue” (ibid.).
Some researchers believe other factors—including La NiƱa and other big weather systems—will overpower any effect global warming might have on hurricanes.

Certainty Does Exist

Global warming does in fact pose a real danger to mankind. Will human beings be able to find a solution? (10) Or will it lead to cataclysmic events?
The Bible reveals that in the near future, there is coming a time of great distress upon the earth: “And there shall be signs in the sun, and in the moon, and in the stars; and upon the earth distress of nations, with perplexity; the sea and the waves roaring; men’s hearts failing them for fear, and for looking after those things which are coming on the earth: for the powers of heaven shall be shaken” (Luke 21:25-26).
In the book of Matthew, Jesus Christ reveals more, stating that this time will be unlike any other in history (11) :  “For then shall be great tribulation, such as was not since the beginning of the world to this time, no, nor ever shall be. And except those days should be shortened, there should no flesh be saved [meaning mankind would become extinct]” (24:21-22).
This time of epic destruction—worse than any other in the history of mankind—is certain to come. Undoubtedly, the effects of global warming will play a role in these events; to what degree remains to be seen.
But beyond the bad news lies the good news—global warming will not result in the extinction of mankind. Human beings will continue to exist, although the earth as we know it will be entirely different! (12) Find out how in our book Tomorrow’s Wonderful World – An Inside View!

AUXILIARY
USES

1) Will
100% certainty
Estimating how much of these gases will be emitted in the future is difficult
2) be to
Strong expectation
However, even if human beings were to cease emitting heat-trapping gases into the atmosphere
3) would
Preference
Even the low end of this warming projection “would probably be greater than any seen in the last 10,000 years
4) used to
Reapeated action in the past
The computer models used to forecast global climate change are still unable to accurately simulate how things may change at smaller scales.
5)  will
100% certainty
the Arctic will be completely ice-free in the summer.
6) must
Strong necessity
Scientists caution that one must consider questions of climate change over decades
7)  can
Impossibility
(negative only)
A particularly rough hurricane season or two cannot be blamed on global warming
8) will
100% certainty
they will be stronger if the oceans are warmer.
9)  may
Less than 50% certainty
The strongest hurricanes in the present climate may be upstaged by even more intense hurricanes over the next century as the earth’s climate is warmed by increasing levels of greenhouse gases in the atmosphere
10)  will
Polite request
Will human beings be able to find a solution?
11)  will
100% certainty
stating that this time will be unlike any other in history
12) will
100% certainty
Human beings will continue to exist, although the earth as we know it will be entirely different!


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