ES 200 Final Exam
The Earth's surface receives from the sun approximately 161 Wm^-2 of radiation. It also receives an amount of radiation from the greenhouse gases in the atmosphere. The amount of radiation from the greenhouse gases that is emitted back to the earth's surface is approximately:
342 Wm^-2
The generally accepted concentration of C in plant biomass is:
50 %, but it can vary from the high 30's to the low 50's
Which most accurately describes the K-T Extinction Event?
A massive meteorite (~15 km diameter) struck the Earth at the boundary between the Cretacous and Tertiary Periods (~65 Ma), causing a nuclear-winter type event that drastically changed the climate causing extinction of many dominant plants and animals.
The mountain pine beetle is an example of:
A native insect species that is expanding its range to higher latitudes due to the warming climate, with potential to devastate forests across northern Canada that were previously protected by cold winters.
Major world biomes include:
ALL OF THE ABOVE: a. Oceans, freshwater bodies, and coastal ecosystems b. Polar tundra and cryosphere c. Deserts, steppes, and Mediterranean ecosystems
Heat in the oceans is distributed from the equator to the poles, driving the climate system. This is accomplished by:
ALL OF THE ABOVE: a. Short-term surface currents such as the Gulf Steam. b. Long-term deep currents, such as the Thermo-Haline Circulation. c. Stochastic, periodic events such as El Nino and even hurricanes.
Savannas and grasslands:
ALL OF THE ABOVE: a. Cover about 30 % of the global land area b. Are often mixtures of co-existing trees and grasses, with trees increasing due to recent land use change c. May experience decreases in NPP in the tropics and increases in the temperate zone in response to warming
The goods and services provided by coastal ecosystems:
ALL OF THE ABOVE: a. Depend on the structure and function of the ecosystem, and can be divided into use and non-use values. b. Can be influenced by human impacts on ecosystem structure and function. c. Have been given an economic value for only some goods and services, but not all.
Which of the following is an example of ecosystem resilience?
Ability of a freshwater lake to remain in a clear-water condition despite the addition of excess nutrients from agricultural runoff, at least until some threshold of water-column nutrient concentration is exceeded.
The definition of "biome" is:
An area of Earth that can be classified by the major plants and animals that live in it and the dominant temperature and moisture regimes.
Which of the following energy sources are cheaper to use than coal for producing electricity? b. On-shore wind turbines c. Advanced natural gas systems
BOTH
Humans are economic creatures by nature. This is evidenced by such things as:
BOTH A AND B: a. "Cahokia", largest urban center of Mississippian culture, declined after 1250 AD due to natural resources depletion. b. Current world gross domestic product, which has increased from about 1 to 80 trillion US dollars from about 1960 to 2017.
The Seuss Effect is used to explain why fossil fuels are the major source responsible for rising carbon dioxide levels in the atmosphere. The Seuss Effect shows that the levels of _________ are decreasing due to dilution of carbon dioxide from fossil fuels which contain no ___________. [Same answer for both blanks]
C-14
Global warming potential (GWP) is a way to rank the radiation absorbing power of a greenhouse gas. Which of the following gases has the lowest GWP value?
CO2
Methane concentrations in the atmosphere have risen by 15% since 1980. Methane is formed when bacteria "eat" or decompose organic matter under anaerobic conditions. In addition to organic carbon, bacteria need ___________ to form methane.
CO2
Representative Concentration Pathways (RCPs) are emission scenarios that modelers use to estimate potential temperatures in the future. Which of the following are used in developing a given RCP scenario?
CO2, N2O, and CH4
The "biological pump" can best be described as:
Carbon and nutrient fluxes to great depths of the ocean water column, and eventual burial in sea floor sediments, due to "leakage" of marine food webs of the euphotic zone, based on photosynthesis by phytoplankton, consumption by zooplankton, and higher trophic levels.
Pre-Cambrian time:
Comprises the Archean, Hadean and Proterozoic Eons, about 4 Gy in duration, representing 7/8 of Earth's geologic history.
Climate models have been developed to better understand Earth's climate system. There are three major groups of models. One group of models includes computations of the various biogeochemical cycles that include the carbon cycle, sulphur cycle, and ozone. This group is best for simulating past and future climates and represents the state of the art climate models. The name for this group of models is:
Earth System Models (ESM)
Protection of human communities from extreme sea level, storm surges, flooding, etc., is an important service provided by coastal ecosystems, which may also simultaneously act to mitigate climate change and increase resilience to future hazards. What are the mechanisms by which this protection is achieved?
Energy dissipation/wave attenuation, C uptake/burial, sediment accretion/stabilization, vegetative growth.
Boreal forest responses to climate change/global warming include expanding the southern distribution limit to lower latitudes, decreasing fire frequency, and lower NPP.
FALSE
Extensive experimentation has shown that elevated atmospheric CO2 tends to decrease forest productivity, whereas high tropospheric O3 increases it.
FALSE
Globally, wetlands occupy 45 % of the terrestrial land area, but only store 3 % of soil organic C.
FALSE
In terms of ecosystem equilibrium, managed ecosystems are more-or-less in equilibrium with the physical environment and associated ecosystems, and provide broad ecosystem services.
FALSE
Ocean surface waters, that is the first 100 m of depth, are uniformly mixed in terms of temperature, salinity, nutrient concentrations, and light availability.
FALSE
Throughout the Phanerozoic, the last ~540 million years of Earth's geologic history, the distribution of the continents around the globe and the climate have remained very stable.
FALSE
Wein's Law states that warmer bodies give off radiation at longer wavelengths than cooler bodies.
False
The acronym FACE stands for:
Free-Air Carbon Dioxide Enrichment
In terms of human consumption of fish from the oceans:
Global demand increased from 20 million tons to over 160 million tons, with almost half of that being supplied by aquaculture in recent years.
The phrase "Planet Earth Quo Vadis?" basically means:
Humans are at a crossroads between choosing to use science and a sense of justice to engineer a sustainable, equitable future or to continue mining the environment unsustainably.
A major source of climate change assessments is the IPCC whose full name is:
Intergovernmental Panel on Climate Change
The ____________ shows the changes in carbon dioxide concentration in the atmosphere over time.
Keeling curve
How have climate models shown that human activities have caused global average temperature to rise?
Model results only match observations when human impacts, such as greenhouse gas concentrations, are included.
Oxygen isotopes are used to estimate temperatures of the past. The ratio of 18O to 16O (18O/16O) is measured as a proxy for temperature. During colder periods the ratio of 18O/16O in ocean water is larger than in warmer periods because:
More 16O in water is locked up in ice on land.
The carbonate chemistry of seawater plays a role in ocean acidification, in that as atmospheric CO2 concentration rises:
More CO2 diffuses into seawater, decreasing the pH (acidification), which decreases the concentration of carbonate ion (CO32-), which causes the dissolution of carbonate structures (such as shells and coral reefs) to maintain chemical equilibrium.
Of the RCP scenarios shown below, which has the highest emissions associated with it? RCP 2.6 RCP 5.0 RCP 8.5
RCP 8.5
If a certain greenhouse gas has a radiative forcing value of 1 Wm-2, how much of a temperature change could be attributed to this? [Hint: use the climate sensitivity parameter.]
Rise of 0.4 oC
"Snowball Earth" refers to:
Several episodes in Earth's deep geologic history where global cooling prevailed (2.3 Ga, 750 to 580 Ma), in which ice extended from the poles to equator and the mean annual temperature was -50 degrees C.
"Coastal squeeze" refers to the phenomenon whereby:
Shoreline erosion and natural sand migration in response to sea-level rise causes seaward land loss of coastal barrier islands, narrowing them and threatening human settlements
The definition of ecosystems is:
Specific assemblages of populations of organisms forming communities in a geographic area resulting from ecological processes operating over evolutionary time, interacting with the physical environment.
Climate forcing agents are things that can cause Earth's temperature change. Some forcing agents cause the Earth to warm by absorbing radiation and re-emitting it. Other forcing agents cause Earth's temperature to cool. Which of the following cause Earth's temperature to cool when they are in the atmosphere?
Sulphuric acid, nitric acid, volcanic particles ejected during eruptions
Which statement(s) best characterize(s) the global C cycle?
THESE: a. A pool of C is a standing stock of C, while a flux is movement of C between pools. c. In terrestrial ecosystems, the largest pool of C is in soil (1500-2400 Pg) compared to vegetation (450-650 Pg).
The term "Global Change" refers to the fact that:
THESE: a. Climate change is just one of many ways that modern society is affecting the environment, possibly decreasing Earth's capacity to continue providing important ecosystem services. c. There is a huge patch of plastic garbage floating in the Pacific Ocean.
Albedo is an important control over Earth's surface energy budget by reflecting incoming solar energy back to the atmosphere.
THESE: a. Dark forests have relatively low albedo c. Ice and snow covered surface have very high albedo
North Carolina is unique in that the northern and southern zones of the coastal plain experience different rates of sea level rise (SLR). Which of the following best describes the situation?
THESE: b. North Carolina experiences some of the highest rates of sea level rise globally. c. The Northern coastal zone experiences both eustatic sea level rise, that is expansion due to warming, plus isostatic rebound of the tectonic plate due to retreat of Pleistocene glaciation.
"Boreal refugia" refers to unique ecosystems typical of much higher latitudes and colder climates that have persisted since the last glacial maximum ~25,000 years ago due to specialized physiographic settings. The spruce-fir-sugar maple forests of the North Carolina Mountains, that very closely resemble forests in northern Michigan, are good examples and are highly threatened by continued climate warming.
TRUE
Although not officially recognized by international scientific societies responsible for naming conventions of Earth's geologic history, many scientists think we are living in a new geologic epoch called the "Anthropocene" because the cumulative impact of human activities on the planet rivals that of geologic forces.
TRUE
IPCC projections of responses of agricultural systems to the changing climate include yield declines, movement to higher latitudes, and accompanying socio-economic adjustments/stress.
TRUE
Stromatolites are dome-shaped structures formed by microbial mats that exist in the fossil record as evidence of early photosynthetic Life on Earth, but they are also currently being formed in real-time in such places as western Australia.
TRUE
The Paleocene-Eocene Thermal Maximum was a period of extreme global warming (+15 oC relative to today) that occurred about 55 Ma due to rapidly rising atmospheric CO2/CH4 from vast coal swamps and volcanism of shifting tectonic plates. Often studied as an analog for today's period of rapid global warming.
TRUE
The first US mining boom occurred in the Upper Peninsula of Michigan (1840-1965) and holds lessons for today's society regarding environmental sustainability, human diversity and social justice, and environmental legacies left to future generations.
TRUE
Holdridge Life Zones are determined by a system of bio-climatic land classification based on:
Temperature, precipitation, and evapotranspiration
The term "life cycle analysis" refers to:
The accounting of all CO2 and GHG fluxes, and changes in C pools, associated with a given type of land use practice, such as short-rotation coppice culture of trees for bioenergy, to determine the net "climatic footprint" compared to traditional land uses and energy production systems (e.g. fossil fuels).
What is meant by the term "biophysical feedbacks" to the climate system:
The reflectivity (albedo), latent heat exchange (evapotranspiration), sensible heat flux, and atmospheric coupling (aerodynamically rough or smooth vegetation canopies) that control the surface energy budget.
In the scientific method:
The self-correcting nature of science usually means that mistakes or even deceptions do not last long.
Cold upwelling is:
The upwelling of cold, nutrient-rich deep ocean currents, often along the western coasts of continents that sustain extremely high biological productivity and support vibrant fisheries, such as anchovies off the coast of Peru.
Evapotranspiration is:
The water evaporated from a unit area of land that includes the water transpired by plants and evaporation from the soil surface combined.
In the global methane budget:
Total global emissions are 558 Tg, and wetlands account for 167 Tg.
Major world biomes in order of decreasing total global C storage in plant biomass are:
Tropical forests, temperate forests, grasslands/savannas, boreal forests, deserts
Where in the atmosphere are most greenhouse gases found?
Troposphere (approximately 0-6 miles)
Reliable records of air temperature measurements go back about 200 years. To estimate temperatures older than 200 years we have to use proxies that allow us to estimate temperature from them. Examples of proxies include stomata in fossil leaves and tree rings.
True
Temperature anomalies are used because temperatures at individual stations in a region may not be representative of the temperatures in a whole region, but the changes over time at that station are likely to track the changes throughout the region.
True
Temperature anomalies are used to summarize temperature data from around the world. Anomalies are calculated for individual weather stations on a given day by subtracting the temperature on that day from:
a baseline of average temperature determined over a number of years from the same station.
The Archean Eon of Earth's deep geologic past:
a. Occurred 3.8 to 2.5 Ga and saw formation of early continents, abundant liquid water/oceans, and the rise of single-celled prokaryotic organisms that oxygenated the atmosphere through photosynthesis.
Tundra ecosystem responses to climate change include:
a. Warming much more than the global average over the past 100 years b. Permafrost melting and increase in the soil active zone c. Encroachment of woody shrubs and increased NPP d. Positive biophysical feedbacks accelerating the rate of climate change e. Sea ice retreat, stressing marine ecosystems
Greenhouse gases contribute to global warming because they:
absorb and re-emit infrared radiation
Banded-iron formations are:
b. Rocks with alternating red and grey bands of oxidized and reduced forms of iron that formed 3.2 to 2.3 Ga, providing evidence for early evolution of aerobic photosynthesis, from which oxygen accumulated in the atmosphere as a waste product. c. Are found around the world, including northern Michigan, supporting the development of iron mining economies.
Radiative forcing is a measure for how a given 'forcing agent' (e.g., greenhouse gas) has contributed to global temperature rise from the year 1750 to today. Which of the following has the largest radiative forcing value?
carbon dioxide
Methane is a strong greenhouse gas, but its lifespan in the atmosphere is about 10 years. It doesn't last, because it is oxidized to:
carbon dioxide and water vapor
he average temperature and average precipitation over a 30-year period are used to define a region's:
climate
In the U.S. we produce more natural gas than any other fuel source. However, the fuel we use for most of our electricity production is:
coal
The level of carbon dioxide in the atmosphere fluctuates annually. It is highest in the Spring but declines over the summer in the northern hemisphere. This decline is caused by:
deciduous tree leaves taking in carbon dioxide during photosynthesis
Nitrous oxide levels have been increasing in the atmosphere since 1980. This greenhouse gas is created in wetlands when nitrate is being converted to a gas by the process of:
denitrification
Cropland occupies the most land area globally of any land use today.
false
The urban heat island effect has contributed to the largest rise in global temperature.
false
The major source of carbon dioxide emissions from 1960 to today is:
fossil fuels and cement
Reducing the amount of food wasted can reduce global emissions of greenhouse gases. Americans waste most of their food:
in their homes and restaurants
World carbon stocks are the places that hold carbon for some period but do release it so it can be recycled. The place where the most carbon is stored is the:
intermediate and deep ocean
The emission source that produces the least or smallest amount of carbon dioxide emissions of those shown below is: a. oil or petroleum b. natural gas c. coal
natural gas
The isotopes of oxygen differ in the number of _____________ in their nucleus.
neutrons
Energy balance models of the Earth have shown that the amount of incoming energy from the sun is slightly greater than the amount of energy re-emitted back into space. As a result the Earth is warming. Where is most of the excess energy being stored?
ocean
As Earth's temperature rises, the amount of water vapor in the atmosphere increases. This causes more infrared radiation from the earth to be absorbed by the vapor, and this also causes the temperature to rise, leading to increasing amounts of water vapor in the atmosphere. This process is an example of:
positive feedback loop
When moist air hits a mountain it rises, cools, and drops its moisture as rain on one side of the mountain. As the air moves over the mountain, the area it passes over will get less rain over time than the other side of the mountain. This phenomenon is called the:
rain shadow effect
When the Earth's temperature was 10 oC warmer than today's temperature, CO2 concentrations in the atmosphere were probably over twice the levels they are today. These large quantities of CO2 were slowly removed from the atmosphere, cooling the earth, by:
rock weathering reactions which took the CO2 out of the atmosphere and stored it in limestone bedrock containing CaCO3.
The Big Bang Theory states:
that all matter in the universe instantaneously came into existence 13.8 billion years ago, primarily as hydrogen and helium.
The sun emits radiation in the visible range while the Earth emits radiation in the infrared range. This is because:
the sun is hotter than the earth
The major way we in the U.S. use petroleum for our energy needs is:
transportation
As the number of sun spots increases the amount of incoming radiation the Earth receives from the sun also increases.
true
Beach re-nourishment will be used more in the future to offset the effects of sea-level rise.
true
Ephemeral plant tissues are those that grow and are shed on short timescales (months to years), such as leaves and fine roots, creating inputs of carbon into soils important to the formation of soil organic carbon (SOC).
true
Global warming will not necessarily cause more hurricanes to occur, but the hurricanes that do occur will more often be found in categories 4 and 5.
true
Indirect evidence of climate change includes ecosystem change/transition, such as trees and shrubs moving into the Arctic tundra, pond pine forests dying along the coast of North Carolina, and major fisheries moving to higher latitudes.
true
Radiative forcing agents that have negative values in Wm-2 would tend to lower temperatures on Earth.
true
Water vapor can be considered the strongest greenhouse gas because it aborbs more wavelengths of light than any other gas.
true
Approximately 200 to 300 million years ago the Earth's average temperature was thought to be over 10 oC warmer than today's. Mass extinctions occurred. One theory for the warmer temperature is that the atmosphere held high concentrations of CO2 gas. The source for this gas was:
volcanic eruptions that spilled lava over a massive area over a 1 million-year period.
El Nino events occur periodically when the winds blowing westward across the ocean have become weaker or changed direction. When these events occur the water off the west coast of South America becomes _______________.
warmer
The Stefan-Boltzman Law says that:
warmer bodies give off more radiation (more Wm-2) than colder bodies.
Sea level is rising as global temperatures rise. The causes of sea level rise include the melting of ice sheets as well as glaciers. Another and potentially larger cause of sea level rise is:
water expands on warming
Which of the following include major greenhouse gases?
water vapor, methane, nitrous oxide
The largest single source of methane is (are):
wetlands
