Hazard Exploration #4—Climate Change: Attempt review

My Courses / ERTH031004-S23R-5103 / Week 5—Natural and Anthropogenic Climate Change — due 6 March / Hazard Exploration #4—Climate Change ERTH 0310-04 The Violent Earth Spring 2023 Question 1 Correct Mark 1.00 out of 1.00 Flag question Question 2 Correct Mark 1.00 out of 1.00 Flag question Question 3 Correct Mark 1.00 out of 1.00 Flag question Question 4 Incorrect Mark 0.00 out of 1.00 Flag question Question 5 Correct Mark 1.00 out of 1.00 Flag question Question 6 Correct Mark 1.00 out of 1.00 Flag question Question 7 Correct Mark 1.00 out of 1.00 Flag question Question 8 Correct Mark 1.00 out of 1.00 Flag question Question 9 Correct Mark 1.00 out of 1.00 Flag question Question 10 Correct Mark 1.00 out of 1.00 Flag question Question 11 Incorrect Mark 0.00 out of 1.00 Flag question Question 12 Correct Mark 1.00 out of 1.00 Flag question Question 13 Correct Mark 1.00 out of 1.00 Flag question Question 14 Correct Mark 1.00 out of 1.00 Flag question Question 15 Correct Mark 1.00 out of 1.00 Flag question Question 16 Correct Mark 1.00 out of 1.00 Flag question Question 17 Correct Mark 1.00 out of 1.00 Flag question Question 18 Correct Mark 1.00 out of 1.00 Flag question Question 19 Correct Mark 1.00 out of 1.00 Flag question Question 20 Incorrect Mark 0.00 out of 1.00 Flag question Started on Thursday, 2 March 2023, 10:26 PM State Finished Completed on Thursday, 2 March 2023, 10:37 PM Time taken 10 mins 39 secs Marks 20.00/23.00 Grade 86.96 out of 100.00 Which statement correctly describes the most recent Ice Age? -- Background from the Overview (Also see text sections 12.1-12.4) Ice Ages & Glaciations... What's the di ff erence? The amount of ice on land grows and shrinks with changes in the global climate. As long as there is ice on earth's surface, we are experiencing an Ice Age. Changes in the amount of ice happen somewhat rapidly, relative to plate motion or rock formation. The last glaciation happened only 20-25,000 years ago, and about 30% of Earth's land area was covered with ice. Today, melting has decreased that number to only 10%, so earth scientists say that we are in an interglacial period. If you enjoy skiing in the Sierra Nevada or the Colorado Rockies, you'll see many breathtaking landforms that were carved by ice over the course of many cold glaciations. Together, this sequence of glaciations (or glacial periods which are separated by interglacial periods) is referred to as an ICE AGE. We are currently still in an ice age, but the ice is melting rapidly! The majority of these jagged landforms are less than two million years old, because the current ice age began during a time that geologists call the Pleistocene Epoch . The Pleistocene was a time of widely fluctuating temperatures, with both cold glacial and warmer interglacial periods, as shown in the diagram. The Pleistocene ended 14,000 years ago with rapid global warming, the melting of huge continental ice sheets, and a corresponding rise in sea level. Since then, we have been in the warmer, interglacial Holocene Epoch . Warmer temperatures are recorded through time by patterns of sea level rise and fall, which geologists can measure using the chemistry of rocks and ice. The curve below shows rising and falling sea level over the past >400,000 years. Currently, we are warm temperatures correspond with the peaked portion of the sea level curve shaded in blue on the far right below, labeled "current sea level". While we normally would expect the next deep-cooling glacial period to begin within a few thousand years, human-caused global climate change may seriously interfere with this natural cycle. Although we are currently experiencing an interglacial, there is still ice on the planet, so we are still in an Ice Age. Again, the figure above shows sea level changes, not global temperature changes, but the two are interlinked. During glacial periods, ice accumulates on land and sea levels drop as water transfers from oceans to land. Then, during warmer interglacials, large expanses of ice melt adding water to the global ocean and raising sea levels. Additional Resources: For those who want to learn more... read all about this period of climate change here: https://www.livescience.com/40311-pleistocene-epoch.html Select one: a. A time called the Quaternary Period (beginning with the Pleistocene and including the Holocene) when ice has advanced and retreated many times.  b. A time when ice exists on the surface of the planet Earth. c. A time tens of millions of years ago called the Cretaceous when ice covered most of the land d. The Holocene Epoch, which began 14 thousand years ago, over which ice covered much land. Your answer is correct. The most recent past glaciation of our current Pleistocene Ice Age began about _______ years ago. (See the Overview resources provided in Question 1) Select one: a. 25,000  b. 1 million c. 2.5 million d. 50,000 e. 500,000 Your answer is correct. Approximately what percentage of the Earth was covered by ice during the last Pleistocene glaciation? (See resources provided in Question 1) Select one: a. 50% b. 30%  c. 20% d. 10% e. There were no ice ages during the Pleistocene f. 100% Global Glacial Coverage During the LGM Greenland Ice Sheet Siberian Ice Sheet Cordileran Ice Sheet Laurentide Ice Sheet Scandinavian Ice Sheet Patagona Ice Sheer Gutt din Sunda land bridge Satrul land bridge Antarctic Ice Sheet Image Source: http://www.humberriver.ca/globalice.html The following super cool video shows how global changes in sea level over the past 20,000 years brought about gradual changes to the shape of the San Francisco bay and the California coastline! Please watch repeatedly to your heart's content. Which statement best describes the level of the sea now compared with 20,000 years ago (at the peak of the last glacial period or glaciation known as the Tioga glacial advance in California)? Select one: a. Sea level was the same as it is today b. Sea level was higher than it is today due to less ice on land and was flooding low-lying areas c. Sea level has high but falling steadily as glaciers continued to grow d. Sea level was lower than it is today due to more ice on land, and rivers flowed in what are now estuaries (i.e. marine embayments that fill old river valleys) e. Sea level was lower than it is today due to less ice was on land, and rivers flowed in what are now estuaries (i.e. marine embayments that fill old river valleys)  Report a problem with this video  SF Bay Flood Your answer is incorrect. Consider the video in Question 4... Over the past few thousand years, how, if at all, has sea level been changing? Select one: a. all of these b. It has remained about the same. c. none of these d. It has been falling. e. It has been rising.  Which statement best describes the later Holocene period? -- Background Resources (from Overview): The Pleistocene ended 14,000 years ago with rapid global warming, the melting of huge continental ice sheets, and a corresponding rise in sea level. Since then, we have been in the warmer, interglacial Holocene Epoch (see the peaked portion of the curve shaded in blue on the far right below ). While we would normally expect the next deep-cooling glacial period to begin within a few thousand years, human-caused global climate change may seriously interfere with this natural cycle. The figure above shows sea level changes, not global temperature changes, but the two are interlinked. During glacial periods, ice accumulates on land and sea levels drop as water transfers from oceans to land. Then, during warmer interglacials, large expanses of ice melt adding water to the global ocean and raising sea levels. Select one: a. An interglacial cooling period that was accentuated by the Industrial Revolution b. A glacial warming period that was accentuated by the Industrial Revolution c. An interglacial warming period that that was accentuated by the Industrial Revolution  d. A glacial cooling period that was accentuated by the Industrial Revolution Your answer is correct. One fantastic place to see geologic evidence of past glaciers that covered high elevations in California is Yosemite National Park. For some awesome views and some examples of these geologic features at Olmsted Point (yep, it's beautiful) please watch this short video: https://www.nps.gov/media/video/view.htm?id=002282B8-DC7D-2C26-BB62AEA212969C12 At Olmstead Point in Yosemite National Park (also with a great view of Half Dome!) are _____________ and ____________ which are both evidence of a glacier at this location in the past. Select one: a. hanging valleys and waterfalls b. crevasses and medial moraines c. eskers and lateral moraines d. erratics and striations  Your answer is correct. One hazardous phenomenon in Yosemite related to ice every winter can be encountered at Yosemite Falls in Yosemite Valley. Here we can see frazil ice flows, which are super unique and cool... But also very dangerous. Learn more here: https://www.nps.gov/media/video/view.htm?id=6F8B3C8C-EF6B-7E9E-A59DF5B55E60A27A Which of the following is NOT an explanation of its inherent dangers? Select one: a. Frazil ice flows like lava. b. Frazil ice can pile up like snow, but it is completely unconsolidated. c. Frazil ice may provide a thin cover over deep, icy cold water. d. Frazil ice forms a beautiful cone below a waterfall.  e. None of these Your answer is correct. Let's go over some of the basic concepts related to our earth's atmosphere and the phenomenon of global warming. The most abundant element in the atmosphere is _____________. See textbook section 12.3 for an overview of the atmosphere! Select one: a. Hydrogen b. Nitrogen  c. Carbon d. Oxygen The search for life on other planets for decades highlights the fact that the occurrence of oxygen in our atmosphere is pretty special! What is considered the origin or first significant source of Earth’s oxygenated atmosphere, which has proved useful for our survival? https://www.scientificamerican.com/article/origin-of-oxygen-in- atmosphere/#:~:text=The%20answer%20is%20tiny%20organisms,carbohydrates%20and%2C%20yes%2C%20oxygen Select one: a. late great asteroid bombardment b. anaerobic "extremophile" cyanobacteria munching on methane and emitting oxygen  c. lightning hitting the ocean for billions of years and splitting water molecules d. aerobic organisms using oxygen dissolved in seawater and emitting carbon dioxide e. We still rely on plants for oxygen today! See your textbook for more on photosynthesis, a process fundamental to our existence! During photosynthesis, plants release _________ using sunlight, water and ________ to create sugars. You may prefer these videos! https://www.youtube.com/watch?v=zWO-bTi6u8M https://www.youtube.com/watch?v=g78utcLQrJ4 Select one: a. Oxygen, Carbon Dioxide b. Carbon Dioxide, Oxygen c. Oxygen, Nitrogen d. Carbon Dioxide, Methane e. Methane, Carbon Dioxide  Coal and petroleum products (fossil fuels) are a powerful resource of ___________ and energy. Following _________ plants and animals are buried and "stored" underground for millions of years leading to the formation of these byproducts. See textbook sections 12.5-12.6 for more on the greenhouse e ff ect & global warming! Select one: a. ozone, nuclear reactions b. carbon, magnetic reversals c. ozone, the sun d. carbon, death  e. oxygen, death The greenhouse e ff ect _____________. See textbook sections 12.5-12.6 for more on the greenhouse e ff ect & global warming! Select one: a. never really varies in strength b. is a recent development resulting from the burning fossil fuels c. has made the Earth the warm and cozy long before humans developed  d. is mysterious and not understood e. is unique to the planet Earth The fundamental, primary argument in favor of anthropogenic or industrial cause for our current climate changes is synchronous and dramatic shift in the chemistry of the atmosphere. The current spike in temperature coincides with a major spike in atmospheric greenhouse gases and the rise of the industrial revolution. Earlier oscillations in the amount of atmospheric greenhouse gases also coincided with temperature changes. For the past 40 million years, these durations were similar, as expected, to known glacial cycles. Highly recommended quick reading: http://www.climatecentral.org/news/the-last-time-co2-was-this-high-humans-didnt-exist-15938 Data Sources: 1. (blue) Vostok ice core : Fischer, H., M. Wahlen, J. Smith, D. Mastroianni, and B. Deck (1999). "Ice core records of Atmospheric CO2 around the last three glacial terminations". Science 283 : 1712-1714. 2. (green) EPICA ice core : Monnin, E., E.J. Steig, U. Siegenthaler, K. Kawamura, J. Schwander, B. Stau ff er, T.F. Stocker, D.L. Morse, J.-M. Barnola, B. Bellier, D. Raynaud, and H. Fischer (2004). "Evidence for substantial accumulation rate variability in Antarctica during the Holocene, through synchronization of CO2 in the Taylor Dome, Dome C and DML ice cores". Earth and Planetary Science Letters 224 : 45- 54. doi : 10.1016/j.epsl.2004.05.007 3. (red) Law Dome ice core : D.M. Etheridge, L.P. Steele, R.L. Langenfelds, R.J. Francey, J.-M. Barnola and V.I. Morgan (1998) "Historical CO2 records from the Law Dome DE08, DE08-2, and DSS ice cores" in Trends: A Compendium of Data on Global Change . Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, U.S. Department of Energy, Oak Ridge, Tenn., U.S.A. 4. (cyan) Siple Dome ice core : Neftel, A., H. Friedli, E. Moor, H. Lötscher, H. Oeschger, U. Siegenthaler, and B. Stau ff er (1994) "Historical CO2 record from the Siple Station ice core" in Trends: A Compendium of Data on Global Change . Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, U.S. Department of Energy, Oak Ridge, Tenn., U.S.A. 5. (black) Mauna Loa Observatory, Hawaii : Keeling, C.D. and T.P. Whorf (2004) "Atmospheric CO2 records from sites in the SIO air sampling network" in Trends: A Compendium of Data on Global Change. Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, U.S. Department of Energy, Oak Ridge, Tenn., U.S.A. Which of the following is a greenhouse gas? See textbook sections 12.5-12.6 for more on the greenhouse e ff ect & global warming! Select one: a. Sulfur Dioxide b. Carbon Dioxide c. All of these  d. Nitrous Oxide e. Methane Over the past 30 years humans have made progress in stopping damage to the ozone layer by curbing the use of certain chemicals. But more remains to be done to protect and restore the atmospheric shield that sits in the stratosphere about 9 to 18 miles (15 to 30 kilometers) above the Earth's surface. Atmospheric ozone absorbs ultraviolet (UV) radiation from the sun, particularly harmful UVB-type rays. Exposure to UVB radiation is linked with increased risk of skin cancer and cataracts, as well as damage to plants and marine ecosystems. Atmospheric ozone is sometimes labeled as the "good" ozone, because of its protective role, and shouldn't be confused with tropospheric, or ground-level, "bad" ozone, a key component of air pollution that is linked with respiratory disease. Ozone (O ) is a highly reactive gas whose molecules are comprised of three oxygen atoms. Its concentration in the atmosphere naturally fluctuates depending on seasons and latitudes, but it generally was stable when global measurements began in 1957 . Groundbreaking research in the 1970s and 1980s revealed signs of trouble. Ozone threats and 'the hole' In 1974, Mario Molina and Sherwood Rowland , two chemists at the University of California, Irvine, published an article in Nature detailing threats to the ozone layer from chlorofluorocarbon (CFC) gases. At the time, CFCs were commonly used in aerosol sprays and as coolants in many refrigerators. As they reach the stratosphere, the sun's UV rays break CFCs down into substances that include chlorine. The groundbreaking research—for which they were awarded the 1995 Nobel Prize in chemistry —concluded that the atmosphere had a “finite capacity for absorbing chlorine” atoms in the stratosphere. One atom of chlorine can destroy more than 100,000 ozone molecules, according to the U.S. Environmental Protection Agency, eradicating ozone much more quickly than it can be replaced. Molina and Rowland’s work received striking validation in 1985, when a team of English scientists found a hole in the ozone layer over Antarctica that was later linked to CFCs. The "hole" is actually an area of the stratosphere with extremely low concentrations of ozone that reoccurs every year at the beginning of the Southern Hemisphere spring (August to October). Spring brings sunlight, which releases chlorine into the stratospheric clouds. Aerosol from cans sometimes contains ozone-depleting substances called chlorofluorocarbons, or CFCs. PHOTOGRAPH BY MARK THIESSEN The ozone layer’s status today Recognition of the harmful e ff ects of CFCs and other ozone-depleting substances led to the Montreal Protocol on Substances That Deplete the Ozone Layer in 1987, a landmark agreement to phase out those substances that has been ratified by all 197 UN member countries. Without the pact, the U.S. would have seen an additional 280 million cases of skin cancer, 1.5 million skin cancer deaths, and 45 million cataracts—and the world would be at least 25 percent hotter. More than 30 years after the Montreal Protocol, NASA scientists documented the first direct proof that Antarctic ozone is recovering because of the CFC phase-down: Ozone depletion in the region has declined 20 percent since 2005. And at the end of 2018, the United Nations confirmed in a scientific assessment that the ozone layer is recovering, projecting that it would heal completely in the (non-polar) Northern Hemisphere by the 2030s, followed by the Southern Hemisphere in the 2050s and polar regions by 2060. Monitoring of the ozone layer continues, and it’s finding that the recovery may not be as straightforward as hoped. A study in early 2018 found that ozone in the lower stratosphere unexpectedly and inexplicably has dropped since 1998 , while another pointed to possible ongoing violations of the Montreal pact. The world is not yet in the clear when it comes to harmful gases from coolants. Some hydrochlorofluorocarbons (HCFCs), transitional substitutes that are less damaging but still harmful to ozone, are still in use. Developing countries need funding from the Montreal Protocol's Multilateral Fund to eliminate the most widely used of these, the refrigerant R-22. The next generation of coolants, hydrofluorocarbons (HFCs), do not deplete ozone, but they are powerful greenhouse gases that trap heat, contributing to climate change . Though HFCs represent a small fraction of emissions compared with carbon dioxide and other greenhouse gases , their planet-warming e ff ect prompted an addition to the Montreal Protocol, the Kigali Amendment , in 2016. The amendment, which came into force in January 2019, aims to slash the use of HFCs by more than 80 percent over the next three decades. In the meantime, companies and scientists are working on climate-friendly alternatives, including new coolants and technologies that reduce or eliminate dependence on chemicals. PUBLISHED APRIL 18, 2019 by National Geographic Depletion of ozone layer __________________. See textbook sections 12.5-12.6 for more on the greenhouse e ff ect & global warming! Select one: a. exposes the surface of the Earth to more UV light which is harmful to many life forms b. can cause increased rates of skin cancer c. could cause major disruptions to food webs d. all of the above  3 Choose the most complete and accurate response. This week's video is an outstanding overview of our current climate change situation. Also, see textbook sections 12.5-12.6 for more on the greenhouse e ff ect & global warming! Evidence indicates that global climate change ___________. Select one: a. is due to human practices b. is natural and has been occurring since the Earth has formed c. is natural and accelerated or altered by human practices  d. will not a ff ect the weather since climate and weather are separate e. The glaciers in Yosemite National Park are our closest examples of a living glacierr. We can quickly learn about Yosemite's glaciers and consider the impact of climate changes on these vestiges of past cold periods by browsing this great summary... https://www.nps.gov/yose/learn/nature/glaciers.htm . Please don't miss the animatio n! Which statement best describes the overall historic trend in Yosemite mountain glacier ice cover? Select one: a. Increasing in some areas b. Remaining steady c. Decreasing in most areas  d. Decreasing in some areas e. Increasing in most areas Your answer is correct. Ice and glaciers are light in color and their reflectivity influences the weather and climate, too. The color white reflects sunlight (heat) more than darker colors, and as ice is so white, sunlight is reflected back out to the sky, which helps to create weather patterns. Ice is very white, and since white reflects sunlight (and thus, heat), large ice fields can determine weather patterns. Air temperatures can be higher a mile above ice caps than at the surface, and wind patterns, which a ff ect weather systems, can be dramatic around ice-covered landscapes. As snow progressively melts over periods of years, centuries, and even millenia, and earth's surface become ___________ reflective, and in turn, the earth's atmosphere __________. Select one: a. less, cools b. more, cools c. same, cools d. less, warms  e. more, warms Some glacier and ice cap facts Bering Glacier in Alaska is the largest glacier in North America. Geologists measure the amount of snow and ice on the planet using NASA satellites. The number is a moving target! Glacial ice covers 10-11 percent of all land. According to the National Snow and Ice Data Center (NSIDC) , if all glaciers melted today the seas would rise about 230 feet (70 meters). During the last ice age (when glaciers covered more land area than today) the sea level was about 400 feet (122 meters) lower than it is today. At that time, glaciers covered almost one-third of the land. During the last warm spell, 125,000 years ago, the seas were about 18 feet (5.5 meters) higher than they are today. About three million years ago the seas could have been up to 165 feet (50.3 meters) higher. Largest surface area of any glacier in the contiguous United States: Emmons Glacier, Washington (4.3 square miles or 11 square kilometers) Ice caps and global water distribution Even though the amount of water locked up in glaciers and ice caps is a small percentage of all water on (and in) the Earth, it represents a large percentage of the world's total freshwater. As these charts and the data table show, the amount of water locked up in ice and snow is only about 1.7 percent of all water on Earth, but the majority of total freshwater on Earth, about 68.7 percent, is held in ice caps and glaciers. One estimate of global water distribution Water source Water volume, in cubic miles Water volume, in cubic kilometers Percent of total water Percent of total freshwater Ice caps, Glaciers, & Permanent snow 5,773,000 24,064,000 1.7% 68.7% Total global freshwater 8,404,000 35,030,000 2.5% -- Total global water 332,500,000 1,386,000,000 -- -- For Week's 9 and 10, we will learn a bit more about water resources. Approximately what percent of the Earth is now covered by ice? https://water.usgs.gov/edu/watercycleice.html Select one: a. 1 to 10%  b. 30% c. 50% d. less than 1% The landmass covered by the most ice is Antarctica at the South Pole, with about 90 percent of the world's ice (and 70 percent of its fresh water). Antarctica is covered with ice an average of 2,133 meters (7,000 feet) thick. If all of the Antarctic ice melted, sea levels around the world would rise about 61 meters (200 feet). But the average temperature in Antarctica is -37°C, so the ice there is not in immediate danger of melting. In fact in most parts of the continent it never gets above freezing. At the other end of the world, the North Pole, the ice is not nearly as thick as at the South Pole. The ice floats on the Arctic Ocean, so most (89%!) of that ice is already underwater. If it melted sea levels would not be a ff ected as much as we might think. There is a significant amount of ice covering Greenland, which would add another 7 meters (20 feet) to the oceans if it melted. Because Greenland is closer to the equator than Antarctica, the temperatures there are higher, so the ice is more likely to melt and contribute to rising sea level. But there might be a less dramatic reason than polar ice melting for the higher ocean level -- the higher temperature of the water. Water is most dense at 4 degrees Celsius. Above and below this temperature, the density of water decreases (the same weight of water occupies a bigger space). So as the overall temperature of the water increases it naturally expands a little bit making the oceans rise. In 1995 the Intergovernmental Panel on Climate Change issued a report which contained various projections of the Quiz navigation Show one page at a time Finish review 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23    Jianci Zhen