Thursday, November 29, 2018

Evidence of Glaciers Past

How vivid are your childhood memories of places visited when you were young? I recall many family trips, church picnics, and personal explorations in Central New York. As time went on, I discovered many facts about the trips, picnics, and locales. Unknown to me at the time was the fact that the Wisconsin Glacier had shaped many of those beautiful spots.

Our past blogs have described many personal childhood adventures. We shall repeat several of these. My brother and I enjoyed living only a half-mile from the Seneca River, one of our childhood fishing venues. The river was part of the hydrologic drainage basin for the famous New York State Finger Lakes—a unique group of eleven narrow north-south oriented deep lakes situated in ancient river valleys. The Wisconsin Glacier Stage reached its peak over 20,000 years ago and covered my childhood home state almost completely with over a mile of solid ice. It left moraines when it retreated—glacial debris which acted as dams to alter drainage to the north. The Seneca River is an example. It eventually drains into Lake Ontario. Ten thousand years ago glacial ice had melted from New York State and was essentially gone from southern Canada 7,000 years ago. The legacy of the Wisconsin glacier remains as the beautiful Finger Lakes region with numerous fascinating leftovers of past glaciations.

One of the most interesting glacial features are drumlins, teardrop shaped hills which taper north to south. The glacier molded these when millions of tons of ice flowed over certain types of soil deposits. Their shape is blunt on the north side and tapered toward the south. My brother utilized our neighborhood drumlins to launch his model gliders.

Some close church friends had a permanent home on Seneca Lake. The bottom of that lake is below sea level. Watkins Glen State Park is the site of a “hanging valley,” in which a valley has been widened by ice moving within it. Tributaries perpendicular to the lake are “left hanging” over a steep valley. They often form waterfalls. Glen Creek has been deep cutting into the rocks surrounding Seneca Lake for thousands of years, forming a two mile long gorge 390´ deep where it begins. It is said to be one of the outstanding beauty spots in the eastern US. Neighboring Cayuga Lake also boasts an exceptional natural spot on its eastern shore. Taughannock Falls plummets downward 215´— higher than Niagara Falls.

My mother did not focus on the scientific realities of historical geology. It is possible she would have been baffled by the exceedingly well-documented age of the universe and our Planet Earth. The Pleistocene epoch lasting from 2.588 million years before the present to the Holocene epoch beginning 11,700 years ago comprises only 0.00057% of our planetary history. Perhaps she believed our planet together with all life forms, including humanity in the image of God, was created in the last 6,000 to 10,000 years. Many believers were raised with that teaching. My father, in contrast, searched out the scientific evidence for a 13.8 billion-year-old universe at age 84 and joyfully endorsed that knowledge.

It is probable that when my mother quoted Psalm 121:1 from her KJV Bible, “I will look unto the hills from whence cometh my help,” she was expressing her intense love and devotion for the Creator of all things. She did not trouble herself with the possibility that our timeless God’s creative processes could span millions of years.

Other wonder-provoking phenomena such as glacial erratics, kettle holes, eskers, glacial wetlands—the dying gasps of great glacial meltwater lakes—and revised drainage patterns are the product of the God of Creation who prepares Earth for the benefit of all humanity and entrusts man with ability to exercise resilience. In the Summer 2001 issue of Life in the Finger Lakes magazine, we read, “Many unique features of the natural scenery of the Finger Lakes area owe their existence to the glacial invasion of the Pleistocene epoch.”         



Friday, November 16, 2018

Ice Age Literacy

In our previous blog post, Air Travel Science, we mentioned traveling by air over the Ohio River. Its course has been altered substantially by the retreat of the Wisconsin ice sheet during the last installment of the Ice Age which began in the last 120,000 years. We remain in the last stage of the Wisconsin glacial event. The retreat of the last continental glacier was but one of many manifestations of major glacial advances and retreats during the Pleistocene epoch—firmly dated by the scientific community as extending from 2.588 million years ago to 11,700 years ago.

For a majority of the 2.588 million years, brief episodes of warmth interrupted the otherwise icy conditions. These episodes were termed “interglacials” and occurred every 41,000 years. Just over 800,000 years ago, there was a major shift in the cycle. Instead of an interglacial every 41,000 years, there was a shift to a 100,000 year cycle. Sudden, short-lived spikes in global temperature of about 10,000 years were followed by slower temperature declines of approximately 90,000 years. The impact of glacial cycles are of enormous benefit to humanity. If they do not occur, modern human life would be impossible to sustain. 

A brilliant Serbian mathematician, astronomer, and climatologist, Milutin Milankovic (1879-1958), proposed that Earth’s glacial cycles were connected to three Earth motions. Obliquity, the axial tilt of Planet Earth which varies between 22.1º  and 24.5º over a period of 41,000 years, results in more extreme seasons.This effect is variable, affecting the distribution of heat at crucial intervals. Obliquity is stabilized by lunar gravity. Eccentricity, the shape of the Earth’s orbit, is affected by gravitation from larger planets Jupiter and Saturn. It results in changes in the degree of solar radiation and occurs at 100,000 and 400,000 year intervals. Finally, axial precession occurs on a cycle of 19,000 to 23,000 years from solar and lunar tidal forces and causes variation in northern hemisphere irradiation.

There are many other factors which relate to glacial cycles. We quote from a research group called FosterLab whose web site effectively deals with the Mid-Pleistocene Transition—the marvelous beneficial change to humanity’s welfare when the ice age cycle transitioned from 41,000 years to 100,000 years: “The Earth system is incredibly complex however and a cascade of feedbacks, some of which are poorly known, amplify the orbital forcing to enact global climate change.” One important amplifier researched by FosterLab is how CO2 is partitioned between the atmosphere and the ocean on these timescales. The ocean holds around 60 times the CO2 of the atmosphere…..On geological timescales the ocean therefore drives atmospheric CO2 change.” Such information may illustrate the logical fallacy of “oversimplified cause” for our contemporary population of global warming enthusiasts obsessed with consumption of fossil fuels producing the “pollutant” CO2. Plant life could not survive without CO2. Natural fluctuations in CO2 have occurred for literally billions of years.

Dr. Hugh Ross of Reasons to Believe has skillfully outlined many possibilities inherent in benefits of the ice ages for humanity in Chapter 15 of his 2016 volume Improbable Planet and in his web series “Miracles of the MId-Pleistocene Transition” parts 1-3. Clearly outlined is the startling transition of the ice age cycle from 41,000 to 100,000 years beginning 800,000 years ago. Ross reviews researchers’ proposals of interplanetary dust, mineral dust, export of organic carbon from oceans, and tectonic events. He adds his own citations of the benefits of the current solar optimum: “We currently enjoy unusual stability in our climate.” We are in the warm phase following an ice age. And yet, we are not too warm. Ross also highlights the apparently supernatural benefits of a remarkable recent paucity of harmful supernovae closer than 5000 light years. Ross states, “Our protection from nearby supernova events appears exceptional.” And how do we explain the “long cool summer” we now experience? The Sun became exceptionally stable in luminosity about 50,000 years ago and seems likely to remain so for the next 50,000 years. “This era of exceptional stability in solar luminosity helped make possible humanity’s launch and development of global, technologically advanced civilization,” writes Ross. World population has ballooned from one billion to 7.5 billion since 1800.

We recommend the above-mentioned resources as a brief introduction for those interested in understanding the meticulous preparation of our unique planetary home by the Creator. The Pleistocene epoch has been termed an Ice Age. It is one of five major ice ages to be identified on Earth. The previous one persisted 100 million years from 360 to 260 million years ago. The Pleistocene Ice Age and the current Holocene epoch of exceptional climatic stability is more significant in terms of contemporary planetary life. In particular, we are aware of the profound impact of the last several glacial epochs since the Mid-Pleistocene, especially the recent Wisconsin glaciation. We observe its effects as evidenced by formation of lakes, new river drainage patterns, erosion, deposition, and many other impressive glacial features. Perhaps most startling is evidence of sea level reductions of up to 400´during the cold periods in the last several tens of thousands of years.

Geologic events such as those we have described may be characterized as miraculous. The degree of fine tuning is virtually impossible to attribute to naturalistic chance. The best examples are solar and cosmic events occurring in concert with the Mid-Pleistocene Transition as well as the many events on Earth which have produced multiple mineral resources since our planet formed 4.5 billion years ago. God is not constrained by time as is humanity. His timeless miracles have been ongoing since the initial creative miracle—the beginning of time, space, matter, and energy 13.8 billion years ago as humans reckon time. That stupendous creative event was the first of many ongoing miracles in the universe we call home in preparation for modern man created “in the image of God.” Full humanity has been present on Earth only 0.00002% of the time since the beginning of Earth’s planetary history. Sustaining miracles for the benefit of humanity still occur.             


Sunday, November 11, 2018

Air Travel Science

Not often do we have the opportunity to travel by air twice in a ten day period. Two airline trips of several days each were separated by a few days at home. All told we traveled nearly 4000 miles via airline.  This entailed six flights, including two connecting flights. My former science students accused their teacher of framing many discussions during field trips through the lens of science—a characterization possessing a large measure of truth. Our goal, however, was that our teacher/student interactions included many relevant topics. Bear with us, readers, as we connect science with our recent air flights.

During the two trips described above, one a memorial service, another a celebration, many opportunities for reviewing the science and history of airline flights became apparent. Some facts announced by the pilot are fascinating. For example, the cruising altitude of 36000 feet at the speed of 600 mph and an exterior temperature of -66ºF on flights passing over several states enable passengers to muse about the progress of air flight science since the Wright Brothers’ initial 12 sec, 120’ flight on a heavier than air vehicle on December 17, 1903.

Our visions out of the undersized plane windows revealed mile after mile of the fascinating patchwork of civilization. Passengers interested in climatology could observe changing agricultural adaptations based on various zones of rainfall, temperature, and altitude. The Ohio River, a young river by geological standards, had its course changed somewhat by the fairly recent Wisconsin glaciation as the ice sheet retreated north upon melting. From the air, we see wonderful meandering rivers and remnants of long vanished rivers revealed by current patterns of vegetation.

Clouds visible from above or from their edges supply a stunning visual touch. Differing temperatures, water vapor content, and air currents provide a plethora of shape, beauty, and color. Knowledge of clouds helps forecast future weather. Often we fly through thick layers of clouds where pilots must entrust knowledge of their location to various electromagnetic phenomena such as radar (microwaves), radio frequencies, and GPS. They use instrument flight rules (IFR).

Understanding virtually every experience we have during air travel relates to scientific knowledge. Turbulence of one degree or another is caused by the interactions of air at different temperatures. Turbulence is a common experience of flyers but it seldom results in any harm. It may, however, cause unease.

Propeller flights provided the default air travel experience from 1928 until about 1960. After that, jet flight gradually replaced propeller flight. Jet air travel was cheaper, safer, and faster. In flight technology, we focus on four factors—all related to Newton’s famous laws of motion. Air travel technology must cope with the effects of (1) lift, (2) weight, (3) thrust, and (4) drag. These factors may be considered esoteric aeronautical knowledge, but most folks identify with these terms in a non-technical manner during air flight. 

In Newton’s First Law, we observe that an object at rest wishes to remain at rest unless acted on by an outside force. This is illustrated by our patient wait on the runway before take-off when directed by the control tower. After takeoff and when sufficient cruising speed has been achieved, there is no need for much additional force to be applied. The plane is speeding forward and tends to keep traveling in the same direction. We might say the airplane is on “cruise control,” minimally affected by the thin, high altitude air. The plane and passengers experience Newton’s First Law—the law of inertia.

In Newton’s Second Law, in order to change the motion of a heavy object, we must apply a force. As an example, if the pilot wants to move multiple passengers and a heavy airplane, he must apply a substantial force. In takeoff experiences, passengers experience an exhilarating force against their back when the pilot suddenly accelerates the heavy airplane at takeoff. The aircraft experiences thrust. In layman’s terms, we may say, “Full speed ahead!”

In Newton’s Third  Law, we observe that every action results in an equal and opposite reaction. In airline parlance, we observe that action in a forward motion is resisted by the force of air acting in the opposite direction. This is illustrated by the influence of drag during takeoff during which air resists forward motion.

Other terms apply to air flight. Lift is experienced when air is forced to travel over the upper curve of the aircraft’s wing. Air at the flat bottom surface of the wing exerts greater pressure. The pressure differential is greater the faster the airplane travels. This effect was described by Daniel Bernoulli in the 18th century. The Bernoulli effect applies to many other phenomena such as a moving frisbee which remains airborne in opposition to the frisbee’s weight as long as it is moving.

Laws of science govern our experiences each time we enjoy an air flight or a multitude of other life experiences. Laws of science are ordered and coherent. We live in a world governed by scientific laws. The Creator has established ordered and coherent laws for our benefit. They bring glory to Himself and enjoyment, order, and coherence to human life. We bow in worship for our Creator, the Author of order and coherence.