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The long-term δ18O trend in benthic foraminifera indicate

> 6 ºC cooling of the deep waters between 50-40 Ma, ice sheet growth after 40-35 Ma, and >7 ºC cooling of the deep waters after 40-35 Ma

Climate differs from weather in that

Climate and climate change occur over longer durations than do weather and weather changes.

The effects of the uplift weathering hypothesis ________ climate-related factors because __________.

Exceed; increased fresh surface area increases the weathering factor

Which of the following is/are true in regards to rates of forcing and climate responses?

Fast change results in slow response & slow change results in fast response

Possible explanations for the malfunction of the Earth's thermostat is (are)

Increased hydrolysis and dissolution from precipitation in the tropics, all continents being located near the equator

What factors contributed to the climactic warming experienced after the asteroid impact 65 Mya?

Increased levels of atmospheric carbon dioxide, inducing a greenhouse effect, and Increased rates of rock and water vaporization, increasing the effect of an already present greenhouse effect.

Back radiation occurs as ________ in the Earth's climate system.

Longwave infrared radiation

Which of the following is a correct statement about Arctic climate in the Cenozoic?

There was palm-like vegetation within the Arctic circle 50 Myr ago, and there was tundra vegetation 2myr ago

Which of the following causes relative global sea level to rise?

Thermal expansion of water molecules

Decisions made in regards to Pangea's general circulation model inputs include

To use modern day sea levels and to use low elevation topography

Chemical weathering of silica-rich rocks on the continents by hydrolysis

Transfers carbon and silica to the ocean where they later are stored in the shells of marine plankton

What is Earth's main sink for solar heat?

Tropic oceans

Cretaceous biota living in the high latitudes included:

Turtles, crocodiles, tropical broad-leafed evergreens, and warm-adapted dinosaurs

The BLAG hypothesis proposes that long-term climate change relies on

Varying rates of seafloor spreading and the storage of dissolved ions in the lithosphere

What explains the annual drops and rises in carbon dioxide atmospheric concentration records?

Vegetation in the Northern hemisphere sequesters large amounts of carbon dioxide in the spring, then respires more in the fall

Characterizing the Cretaceous climate, the geologic record indicates

Warmer temperatures globally

What was the general long-term climate trend in the last 50 Myr?

erratic cooling

Which of the following would be an appropriate archive for reconstructing what the climate was like 50 Myr?

ocean sediment cores

Climate science...

requires an earth system perspective, spans vast temporal and spatial scales

Why does Earth's temperature react strongly to changes in CO2 at the low end of the range, but much less so to changes at the high end of the range?

Strong albedo-temp feedback of snow and ice in an icehouse world, and because co2 saturation potential in the atmosphere

Earth's average surface temperature is

15.5 deg C

The amount of solar radiation that enters the Earth's climate system is

238 W/m2

Which of the following is an example of a biotic proxy that could be used for reconstructing past climate change?

A data set of temperature-sensitive planktonic foraminifera species changes over time at a deep marine site

What process could serve to moderate the global cooling in the last 50 Myr?

A reduction of chemical weathering on land not uplifted due to cooler, drier conditions globally

Ice cores are valuable climatic archives because

Annual layers are often resolvable, which enables age determination and correlation, ice has geochemical proxies of atmosphere of the past, coring sites range from the tropics to the poles

Which of the following correctly describes the relationship between mean annual temperature and leaf shape?

As the temperature warms, there is an increase in the percent of plants with smooth-edged leaves.

Modern day glacial ice can be found

At the poles and at high elevations in the tropics

Why has Earth remained habitable throughout its history?

Because chemical weathering of continental rocks both responds to and modifies the level of CO2 greenhouse gases in the atmosphere over geologic time scales

The Coriolis Effect influences

Both atmospheric and oceanic circulation

The modeled climate of Pangea would have experienced

Cold, dry winters and hot, wet summers

According to Ruddiman, most natural carbon dioxide is expelled from

Convergent and divergent boundaries

Mg/Ca ratios in foraminifera shells

Depend on the temperature of the sea water

The snowball Earth hypothesis

Describes a period between 800 and 550 Myr, during which continental glaciation was widespread, including in the tropics

Sediment archives

Have a temporal resolution dependent on the rate that the sediment accumulated and whether it has been disturbed (mixed-up. after deposition)

Which two major groups of organism are most important to climate reconstructions over the past several million years?

Microfossils of plankton and pollen

Which source of carbon has the potential to cause the most rapid effects on the climate system?

Organic carbon - it can be rapidly trapped and buried in sediment, reducing atmospheric carbon dioxide concentrations.

Cooling, the subsequent development of sea ice, and its impact on the climate system would be an example of

Positive feedback loop

Which of the following is the largest reservoir of carbon in the Earth system today?

Sediments and rocks

Consider the study of past climate change and determine which of the following is correct.

Resolution of climate archives is generally greater in the recent past than the geologic past, the types of climate archives available now are more diverse than they ever have been

A sea level regression

Results in higher erosion rates on the continental margin

Geologic evidence supporting the modeled Pangea climate include

Rock salt deposits, beds of oxidized sedimentary rocks, and a lack of characteristics of long-term glaciation

What characteristics are indicative of an asteroid impact?

Small quartz grains exhibiting shock lamellae, ocean sedimentation enriched in iridium

Which of the following is an external driver of Earth's climate?

Solar strength variation

Numerical simulations of past climate occur in an ordered three-step sequence. The order is

Specify boundary conditions, Run a climate simulation, Analyze the climate data output by comparing them with independent geologic data

Which of the following increase the rate of chemical weathering?

Temperature, Precipitation, vegetation

__________________ contradicts the polar position hypothesis.

The absence of glaciation about 400 Mya

Which of the following criteria of the uplift weathering hypothesis is suggested in the geologic archives of the last 50 Myr?

The amount of high-elevation terrain in existence today must be unusually large in comparison with that of earlier intervals.

The most important reason why Venus is much hotter than Earth is because

The carbon dioxide rich atmosphere causes a strong greenhouse effect

Which of the following is the most viable explanation for inconsistencies between Cretaceous geologic target temperatures and model simulation results?

The geologic proxy data used to set target temperatures in the models were compromised by geochemical alteration.

When results from model simulations of Cretaceous climate are compared against the temperature target signal from geologic data

The simulations are in general agreement with the data, but produce a steeper pole-to-equator gradient in temperatures than are supported by the data

What is the correct order of response time from slowest to fastest?

continental ice sheets, deep ocean, sea ice, land surface, atmosphere

What causes Earth's climate to change?

changes in Earth's orbit around the sun, human activities, changes in the strength of the sun, changes in plate tectonics

Supporters of the Gaia hypothesis argue that

life evolved for the purpose of regulating Earth's climate, living organisms played a significant role in regulating the climate

Dating, and therefore correlation, of different sediment sequences may be accomplished using

orbital tuning, radiometric dating of isotopes, fossil record, identification of a marker bed

Climate change science involves research in

paleoecology, chemistry, geophysics, climate history