The origin of ice ages is controversial, with two opposing theories proposed. Robert Berner believes ice ages are caused by long-term decreases in decarbonation reducing atmospheric CO2 levels. Maureen Raymo argues that uplift of mountain ranges like the Himalayas increased weathering, removing CO2 from the air and cooling the climate. Eric Sundquist later concluded both theories may operate, but on different timescales, with steady-state operating over millions of years and non-steady-state during shorter uplift events.
A talk about the climate history of earth, and what may have effected it. Given as part of the exam in Climate Physics course at the University of Aarhus
Antarctic climate history and global climate changesPontus Lurcock
Antarctic climate changes have been reconstructed from ice and sediment cores and numerical models (which also predict future changes). Major ice sheets first appeared 34 million years ago (Ma) and fluctuated throughout the Oligocene, with an overall cooling trend. Ice volume more than doubled at the Oligocene-Miocene boundary. Fluctuating Miocene temperatures peaked at 17–14 Ma, followed by dramatic cooling. Cooling continued through the Pliocene and Pleistocene, with another major glacial expansion at 3–2 Ma. Several interacting drivers control Antarctic climate. On timescales of 10,000–100,000 years, insolation varies with orbital cycles, causing periodic climate variations. Opening of Southern Ocean gateways produced a circumpolar current that thermally isolated Antarctica. Declining atmospheric CO2 triggered Cenozoic glaciation. Antarctic glaciations affect global climate by lowering sea level, intensifying atmospheric circulation, and increasing planetary albedo. Ice sheets interact with ocean water, forming water masses that play a key role in global ocean circulation.
A talk about the climate history of earth, and what may have effected it. Given as part of the exam in Climate Physics course at the University of Aarhus
Antarctic climate history and global climate changesPontus Lurcock
Antarctic climate changes have been reconstructed from ice and sediment cores and numerical models (which also predict future changes). Major ice sheets first appeared 34 million years ago (Ma) and fluctuated throughout the Oligocene, with an overall cooling trend. Ice volume more than doubled at the Oligocene-Miocene boundary. Fluctuating Miocene temperatures peaked at 17–14 Ma, followed by dramatic cooling. Cooling continued through the Pliocene and Pleistocene, with another major glacial expansion at 3–2 Ma. Several interacting drivers control Antarctic climate. On timescales of 10,000–100,000 years, insolation varies with orbital cycles, causing periodic climate variations. Opening of Southern Ocean gateways produced a circumpolar current that thermally isolated Antarctica. Declining atmospheric CO2 triggered Cenozoic glaciation. Antarctic glaciations affect global climate by lowering sea level, intensifying atmospheric circulation, and increasing planetary albedo. Ice sheets interact with ocean water, forming water masses that play a key role in global ocean circulation.
Site of asteroid impact changed the history of life on Earth: the low probabi...Sérgio Sacani
Sixty-six million years ago, an asteroid approximately 9km in diameter hit the hydrocarbon- and
sulfur-rich sedimentary rocks in what is now Mexico. Recent studies have shown that this impact at
the Yucatan Peninsula heated the hydrocarbon and sulfur in these rocks, forming stratospheric soot
and sulfate aerosols and causing extreme global cooling and drought. These events triggered a mass
extinction, including dinosaurs, and led to the subsequent macroevolution of mammals. The amount
of hydrocarbon and sulfur in rocks varies widely, depending on location, which suggests that cooling
and extinction levels were dependent on impact site. Here we show that the probability of signifcant
global cooling, mass extinction, and the subsequent appearance of mammals was quite low after an
asteroid impact on the Earth’s surface. This signifcant event could have occurred if the asteroid hit the
hydrocarbon-rich areas occupying approximately 13% of the Earth’s surface. The site of asteroid impact,
therefore, changed the history of life on Earth.
Presentation given during the kick-off of the TU Delft Climate Institute on March 1st 2012. Sea level rise is one of the reserach topics of the new institute. Dr Bert Vermeersen explained why.
Site of asteroid impact changed the history of life on Earth: the low probabi...Sérgio Sacani
Sixty-six million years ago, an asteroid approximately 9km in diameter hit the hydrocarbon- and
sulfur-rich sedimentary rocks in what is now Mexico. Recent studies have shown that this impact at
the Yucatan Peninsula heated the hydrocarbon and sulfur in these rocks, forming stratospheric soot
and sulfate aerosols and causing extreme global cooling and drought. These events triggered a mass
extinction, including dinosaurs, and led to the subsequent macroevolution of mammals. The amount
of hydrocarbon and sulfur in rocks varies widely, depending on location, which suggests that cooling
and extinction levels were dependent on impact site. Here we show that the probability of signifcant
global cooling, mass extinction, and the subsequent appearance of mammals was quite low after an
asteroid impact on the Earth’s surface. This signifcant event could have occurred if the asteroid hit the
hydrocarbon-rich areas occupying approximately 13% of the Earth’s surface. The site of asteroid impact,
therefore, changed the history of life on Earth.
Presentation given during the kick-off of the TU Delft Climate Institute on March 1st 2012. Sea level rise is one of the reserach topics of the new institute. Dr Bert Vermeersen explained why.
Short presentation for anyone interested in Weather in Australia. We talk about the four seasons, temperatures, activities and natural disasters for your viewing pleasure!
World Religions - Mormonism - JR. ForasterosJR. Forasteros
Is Mormonism a branch of Christianity? Is it another religion? What're the differences? And how much do they matter?
Podcast available at www.jrforasteros.com/world-religions-podcast
Amish A-Z, 26 important aspects of the Amish culture in Holmes Co., Ohio. Based on the book by Lester Beachy, "Our Amish Values: Who we are and what we believe."
Climate Change
Investigation
Manual
ENVIRONMENTAL SCIENCE
CLIMATE CHANGE
Overview
In this lab, students will carry out several activities aimed at
demonstrating consequences of anthropogenic carbon emissions,
climate change, and sea level rise. To do this, students will model
how certain gases in Earth’s atmosphere trap heat and then how
different colors and textures of surfaces reflect differing amounts
of sunlight back into space. They will create models of sea level
rise resulting from melting of sea ice and glacial ice and examine
the effects of this potential consequence of climate change.
Students will critically examine the model systems they used in
the experiments.
Outcomes
• Explain the causes of increased carbon emissions and their likely
effect on global climate.
• Discuss positive and negative climate feedback.
• Distinguish between glacial ice melt and oceanic ice melt.
Time Requirements
Preparation ..................................................................... 15 minutes
Activity 1: Modeling the Greenhouse Effect ................... 30 minutes
Activity 2: Modeling Albedo ........................................... 40 minutes
Activity 3: Sea Ice, Glacial Ice, and Sea Level Rise ....... 30 minutes
2 Carolina Distance Learning
Key
Personal protective
equipment
(PPE)
goggles gloves apron
follow
link to
video
photograph
results and
submit
stopwatch
required
warning corrosion flammable toxic environment health hazard
Made ADA compliant by
NetCentric Technologies using
the CommonLook® software
Table of Contents
2 Overview
2 Outcomes
2 Time Requirements
3 Background
9 Materials
9 Safety
9 Preparation
10 Activity 1
11 Activity 2
12 Activity 3
13 Graphing
13 Submission
13 Disposal and Cleanup
14 Lab Worksheet
Background
For the last 30 years, controversy has
surrounded the ideas of global warming/climate
change. However, the scientific concepts behind
the theory are not new. In the 1820s, Joseph
Fourier was the first to recognize that, given
the earth’s size and distance from the sun,
the planet’s surface temperature should be
considerably cooler than it was. He proposed
several mechanisms to explain why the earth
was warmer than his calculations predicted,
one of which was that the earth’s atmosphere
might act as an insulator. Forty years later,
John Tyndall demonstrated that different
gases have different capacities to absorb
infrared radiation, most notably methane (CH4),
carbon dioxide (CO2), and water vapor (H2O),
all of which are present in the atmosphere. In
1896, Svante Arrhenius developed the first
mathematical model of the effect of increased
CO2 levels on temperature. His model predicted
that a doubling of the amount of CO2 in the
atmosphere would produce a 5–6 °C increase
in temperature globally. Based on the level of
CO2 production in the late 19th century, he
predicted that this change would take place
over thousands of years, if at ...
Climate change is a significant and lasting change in the statistical distribution of weather patterns over periods ranging from decades to millions of years. It may be a change in average weather conditions, or in the distribution of weather around the average conditions (i.e., more or fewer extreme weather events). Climate change is caused by factors such as biotic processes, variations in solar radiation received by Earth, plate tectonics, and volcanic eruptions. Certain human activities have also been identified as significant causes of recent climate change, often referred to as "global warming"
Scientists actively work to understand past and future climate by using observations and theoretical models. A climate record — extending deep into the Earth's past — has been assembled, and continues to be built up, based on geological evidence from borehole temperature profiles, cores removed from deep accumulations of ice, floral and faunal records, glacial and periglacial processes, stable-isotope and other analyses of sediment layers, and records of past sea levels. More recent data are provided by the instrumental record. General circulation models, based on the physical sciences, are often used in theoretical approaches to match past climate data, make future projections, and link causes and effects in climate change.
Describes latest observations of climate by satellites and ground stations and assesses them relative to the possible causes of 'greenhouse gases', world energy use, and latent heat transfer by crop irrigation.
Investigation of cause of climate change. Review of all the evidence from NASA, NSIDC, NOAA and UK Meteorological Office. Calculation of latent heat associated with water vapour emissions from irrigation.
A tsunami in South Wales? The 1607 flood in the Bristol Channel and Severn Es...Prof Simon Haslett
The flood of 1607 was the worst natural disaster ever recorded in the British Isles. The flood affected most of the South Wales coast from Carmarthenshire in the west to Monmouthshire in the east. On the other side of the Bristol Channel and Severn Estuary, parts of Southwest England were also severely affected stretching from North Devon, through to Somerset and Gloucestershire, which together with South Wales amounts to 570 km of coastline. The coastal population was devastated with at least 2000 fatalities according to one of the contemporary sources. In some parts of the coast the population never recovered from the social and economic disaster. But what caused the flood? This seminar looks at historical documentary and geographical fieldwork evidence collected by Professor Simon Haslett and co-workers in proposing that the 1607 flood may have been due to a tsunami.
Getting Published! Exploring strategies, myths and barriers of academic publi...Prof Simon Haslett
Publications are an important aspect of the work of an academic; remaining the principal vehicle through which research is reported, opinions aired, reviews undertaken, and knowledge transferred, and writing is also a useful learning exercise. For many, it also underpins teaching and curricula, means greater success in research grant applications, and a good publication track record is still seen by many institutions as a key recruitment and promotion criteria. Yet traditionally how to get your work published has not been taught, but learnt through trial and error, mainly from rejection by journal editors. This seminar is aimed at inexperienced academic authors and explores and discusses the issues surrounding the strategy and publication of academic work, and addresses some of the myths and barriers that might discourage would-be authors after the research and writing process is complete.
Projection of Wales as an internationally engaged/forward-looking nation.Prof Simon Haslett
Presented at the 'Universities as Global Communities' event at Bangor University on Thursday 13th February 2020. The event was jointly organised by the Learned Society of Wales and Universities Wales, and is part of the 'Wales and the World' series.
Flexible Provision: Rising to Challenges in Learning and Teaching - An Inst...Prof Simon Haslett
Presentation by Professor Simon Haslett at the Annual Learning and Teaching Conference 2015 at the University of Wales Trinity Saint David, Carmarthen Campus.
A presentation by Professor Simon Haslett (University of Wales) at the International University of Malaya-Wales (IUMW) on Wednesday 19th February 2014.
Workshop presentation by Professor Simon Haslett at the University of Wales: Trinity Saint David Research, Innovation, Enterprise & Commercialisation Staff Development Day at the Townhill Campus, Swansea, on Monday 16th December 2013.
Keynote presentation by Professor Simon Haslett at the University of Wales: Trinity Saint David Research, Innovation, Enterprise & Commercialisation Staff Development Day at the Townhill Campus, Swansea, on Monday 16th December 2013.
Exploring Links between Research and Teaching in Higher EducationProf Simon Haslett
A presentation by Professor Simon Haslett, Associate Pro Vice-Chancellor of the University of Wales. The presentation is part of the HEA Research Seminar/Webinar Series, 11th June 2013, at The Higher Education Academy, York. This seminar examines the ways in which research and teaching may be linked in academic practice in Higher Education. It seeks to unravel the various linkages through scholarship, research (both subject-based and pedagogic) and curriculum. The presentation draws upon the presenters’ recent experience as a leader in learning and teaching in Wales, including the activity and contribution of the Research-Teaching Nexus Action Set, and the current challenges to forging and maintaining research-teaching links in Higher Education. He also provides examples of research-teaching links from his own professional practice.
This presentation will help you to think holistically about publishing your research and scholarship. It particularly focuses on targeting publication in academic journals and on the processes for dealing with publication. It is useful for all early stage researchers, whether research students or academic/research staff at the beginning of their career or more experienced staff seeking to develop a publication profile.
Presented at Swansea Metropolitan, University of Wales: Trinity St David on Wednesday 6th March 2013 by Professor Simon Haslett, Associate Pro Vice-Chancellor at the University of Wales.
Presentation by Professor Simon Haslett to the Geographical Association at King's College, Taunton, on Tuesday 15th November 2012.
A presentation based on research featured in 'Killer Wave of 1607' as broadcast by BBC2 Timewatch. The flood of that year in the Bristol Channel and Severn Estuary was the worst ever recorded in the British Isles. The area affected stretched from North Devon, through Somerset and Gloucestershire, and along the South Wales coast from Monmouthshire to Carmarthenshire, some 570 km of coast! The coastal population was devastated with at least 2000 fatalities according to one of the contemporary sources. In some parts of the coast the population never recovered from the social and economic disaster. Simon and his co-worker have used documentary and fieldwork evidence to propose a new interpretation of its cause as a tsunami. The BBC produced a follow-up Timewatch programme entitled 'Britain’s Forgotten Floods' that followed Simon around the British coastline examining further evidence for tsunami impact.
Presentation by Professor Simon Haslett at the University of the Third Age Mendip Hills Study Day at Draycott, Somerset, on 1st March 2012.
Simon Haslett is Professor of Physical Geography and Associate Pro Vice-Chancellor at the University of Wales.
The talk is based on extracts from S. K. Haslett (2010) Somerset Landscapes: Geology and Landforms. Blackbarn Books. Available from:
https://sites.google.com/site/blackbarnbooks/publications/somerset-landscapes-geology-and-landforms
The 2011 Annual Kelliwic Lecture presented by Professor Simon Haslett at Callington Town Hall, Cornwall, on Sunday 29th May 2011. Simon Haslett is Professor of Physical Geography and Dean of the School of STEM at the University of Wales.
Presentation by Professor Simon Haslett at the Aegean Omiros College, Athens, Greece, on Thursday 19th May 2011. Simon Haslett is Professor of Physical Geography and Dean of the School of STEM at the University of Wales.
Lecture by Professor Simon Haslett at the University of Wales Student Research Conference, Cardiff, on Friday 13th May 2011. Simon Haslett is Professor of Physical Geography and Dean of the School of STEM at the University of Wales.
Presentation by Professor Simon Haslett at the University of Wales, Newport, Centre for Excellence in Learning and Teaching (CELT) Writing Retreat Workshop at Gregynog Hall, Wales, on Wedmesday 11th May 2011. Simon Haslett is Professor of Physical Geography and Dean of the School of STEM at the University of Wales. He is also Visiting Professor of Pedagogic Research at the University of Wales, Newport.
A Strategic Approach: GenAI in EducationPeter Windle
Artificial Intelligence (AI) technologies such as Generative AI, Image Generators and Large Language Models have had a dramatic impact on teaching, learning and assessment over the past 18 months. The most immediate threat AI posed was to Academic Integrity with Higher Education Institutes (HEIs) focusing their efforts on combating the use of GenAI in assessment. Guidelines were developed for staff and students, policies put in place too. Innovative educators have forged paths in the use of Generative AI for teaching, learning and assessments leading to pockets of transformation springing up across HEIs, often with little or no top-down guidance, support or direction.
This Gasta posits a strategic approach to integrating AI into HEIs to prepare staff, students and the curriculum for an evolving world and workplace. We will highlight the advantages of working with these technologies beyond the realm of teaching, learning and assessment by considering prompt engineering skills, industry impact, curriculum changes, and the need for staff upskilling. In contrast, not engaging strategically with Generative AI poses risks, including falling behind peers, missed opportunities and failing to ensure our graduates remain employable. The rapid evolution of AI technologies necessitates a proactive and strategic approach if we are to remain relevant.
Unit 8 - Information and Communication Technology (Paper I).pdfThiyagu K
This slides describes the basic concepts of ICT, basics of Email, Emerging Technology and Digital Initiatives in Education. This presentations aligns with the UGC Paper I syllabus.
June 3, 2024 Anti-Semitism Letter Sent to MIT President Kornbluth and MIT Cor...Levi Shapiro
Letter from the Congress of the United States regarding Anti-Semitism sent June 3rd to MIT President Sally Kornbluth, MIT Corp Chair, Mark Gorenberg
Dear Dr. Kornbluth and Mr. Gorenberg,
The US House of Representatives is deeply concerned by ongoing and pervasive acts of antisemitic
harassment and intimidation at the Massachusetts Institute of Technology (MIT). Failing to act decisively to ensure a safe learning environment for all students would be a grave dereliction of your responsibilities as President of MIT and Chair of the MIT Corporation.
This Congress will not stand idly by and allow an environment hostile to Jewish students to persist. The House believes that your institution is in violation of Title VI of the Civil Rights Act, and the inability or
unwillingness to rectify this violation through action requires accountability.
Postsecondary education is a unique opportunity for students to learn and have their ideas and beliefs challenged. However, universities receiving hundreds of millions of federal funds annually have denied
students that opportunity and have been hijacked to become venues for the promotion of terrorism, antisemitic harassment and intimidation, unlawful encampments, and in some cases, assaults and riots.
The House of Representatives will not countenance the use of federal funds to indoctrinate students into hateful, antisemitic, anti-American supporters of terrorism. Investigations into campus antisemitism by the Committee on Education and the Workforce and the Committee on Ways and Means have been expanded into a Congress-wide probe across all relevant jurisdictions to address this national crisis. The undersigned Committees will conduct oversight into the use of federal funds at MIT and its learning environment under authorities granted to each Committee.
• The Committee on Education and the Workforce has been investigating your institution since December 7, 2023. The Committee has broad jurisdiction over postsecondary education, including its compliance with Title VI of the Civil Rights Act, campus safety concerns over disruptions to the learning environment, and the awarding of federal student aid under the Higher Education Act.
• The Committee on Oversight and Accountability is investigating the sources of funding and other support flowing to groups espousing pro-Hamas propaganda and engaged in antisemitic harassment and intimidation of students. The Committee on Oversight and Accountability is the principal oversight committee of the US House of Representatives and has broad authority to investigate “any matter” at “any time” under House Rule X.
• The Committee on Ways and Means has been investigating several universities since November 15, 2023, when the Committee held a hearing entitled From Ivory Towers to Dark Corners: Investigating the Nexus Between Antisemitism, Tax-Exempt Universities, and Terror Financing. The Committee followed the hearing with letters to those institutions on January 10, 202
How to Make a Field invisible in Odoo 17Celine George
It is possible to hide or invisible some fields in odoo. Commonly using “invisible” attribute in the field definition to invisible the fields. This slide will show how to make a field invisible in odoo 17.
Biological screening of herbal drugs: Introduction and Need for
Phyto-Pharmacological Screening, New Strategies for evaluating
Natural Products, In vitro evaluation techniques for Antioxidants, Antimicrobial and Anticancer drugs. In vivo evaluation techniques
for Anti-inflammatory, Antiulcer, Anticancer, Wound healing, Antidiabetic, Hepatoprotective, Cardio protective, Diuretics and
Antifertility, Toxicity studies as per OECD guidelines
Francesca Gottschalk - How can education support child empowerment.pptxEduSkills OECD
Francesca Gottschalk from the OECD’s Centre for Educational Research and Innovation presents at the Ask an Expert Webinar: How can education support child empowerment?
Embracing GenAI - A Strategic ImperativePeter Windle
Artificial Intelligence (AI) technologies such as Generative AI, Image Generators and Large Language Models have had a dramatic impact on teaching, learning and assessment over the past 18 months. The most immediate threat AI posed was to Academic Integrity with Higher Education Institutes (HEIs) focusing their efforts on combating the use of GenAI in assessment. Guidelines were developed for staff and students, policies put in place too. Innovative educators have forged paths in the use of Generative AI for teaching, learning and assessments leading to pockets of transformation springing up across HEIs, often with little or no top-down guidance, support or direction.
This Gasta posits a strategic approach to integrating AI into HEIs to prepare staff, students and the curriculum for an evolving world and workplace. We will highlight the advantages of working with these technologies beyond the realm of teaching, learning and assessment by considering prompt engineering skills, industry impact, curriculum changes, and the need for staff upskilling. In contrast, not engaging strategically with Generative AI poses risks, including falling behind peers, missed opportunities and failing to ensure our graduates remain employable. The rapid evolution of AI technologies necessitates a proactive and strategic approach if we are to remain relevant.
Long-term palaeoclimate: the origin of the ice ages
1. Long-term palaeoclimate: the origin of the ice ages Professor Simon K. Haslett Centre for Excellence in Learning and Teaching Simon.haslett@newport.ac.uk 16rd September 2010
2. Introduction What stimulated the global cooling that led to the development of the continental ice sheets that characterised the Quaternary and other ice ages through geological time? The search for the answer to these major climate questions has generated some fascinating research that has become the focus of much media attention. However, a number of different theories have been proposed to account for the origin of the ice ages, and there is intense argument between the supporters of the different theories – a very controversial topic. This presentation hopes to discuss what caused the ice ages, and describes the radical theories relating to climatic changes.
3.
4. Robert Berner and his colleagues who believe that long-term trends in the carbon cycle coupled with the Greenhouse Effect are responsible.These theories invoke a relationship between atmospheric CO2, tectonic activity, and the carbonate-silicate cycle.
5. Geochemical or steady-state model 1 The ‘geochemical’ or ‘steady-state’ model was proposed by Berner in 1990, and suggests that tectonic activity releases CO2 through a process called decarbonation, which increases atmospheric CO2. This in turn enhances the Greenhouse Effect which results in global warming, and enhances continental weathering. Rocks weather more rapidly in warm/moist conditions. Weathered products are transported to the sea where they promote carbonate (CaCO3) formation (i.e. shells) which sink to the sea-floor. C B A (a) Foraminifera secrete calcareous ‘tests’ and inhabit both the sea-bed and the water column. (b) Cut blocks of fenwood peat. Peat consists of partially decomposed organic material which acts as a sink for carbon because of the anaerobic conditions in which it is found. Note the coin for scale. (c) Volcanic activity releases millions of tonnes of CO2 into the atmosphere every year (Terceira island, Azores).
6. Geochemical or steady-state model 2 In conjunction with the weathering processes themselves (which consume atmospheric CO2), detrital rain in the water column takes carbon out of circulation until the sediments are decarbonated. This process maintains a steady-state relationship between weathering, decarbonation, and atmospheric CO2 levels, and so essentially weathering is controlled by decarbonation. The variation in CO2 throughout the Phanerozoic is apparently related to the relationship of tectonic activity, rise of vascular plants, and the burial of organic matter. The Quaternary ice ages are attributed by Berner (1990) to a general decrease in decarbonation over the last 100 Ma and an increase in the burial of organic matter.
7. Uplift or non-steady-state model 1 Raymoet al.’s (1988) model (called the uplift or non-steady-state model) suggests that CO2 levels are not controlled by decarbonation, and promotes the idea that the process of uplift alone can stimulate weathering, stripping CO2 out of the atmosphere, increasing CaCO3 sedimentation in the oceans, so causing global cooling and the Quaternary ice ages. Thus, this model operates in a non-steady-state because the carbon cycle is being influenced by factors from outside the system (i.e. uplift). Formation of scree slopes indicates physical and chemical weathering and erosional processes acting on a rock face (Andalusia, Spain).
8. Uplift or non-steady-state model 2 During the Late Cenozoic a number of uplift events have occurred (e.g. Tibetan Plateau, Himalayas, Andes, Alps etc) which may have provided the stimuli for global cooling. Indeed there is evidence for increased weathering at this time (e.g. strontium content of deep-sea sediments). Tectonically driven uplift of mountain ranges , e.g. the Alps, has been suggested to have initiated glaciation.
9. Consolidation of the theories Sundquist (1991) constructs a complex ocean-atmosphere-sediment model to evaluate these conflicting theories. He concludes that both of these theories operate in nature, but on different time scales, with the steady-state model operating over longer periods of geological time, whilst the non-steady-state may interfere over shorter periods and specific to uplift events. A useful figure derived from his model is that a lagged response time of 300-400 ka exists between either uplift or decarbonation and increased weathering capable of depleting atmospheric CO2.
10. Practical – Milankovitch cycles 1 Examine the SPECMAP graph below of an oxygen isotope record taken from a deep-sea sediment core (the top of the core is the modern sea-floor surface). Oxygen isotopes vary depending on changes in global ice volume. Using your knowledge of oxygen isotopes and Milankovitch cycles, answer the questions that follow:
11. Practical – Milankovitch cycles 2 Make a copy of the preceding graph. Identify perturbations in the oxygen isotope record due to eccentricity, obliquity and precession cycles (annotate examples on your graph where appropriate). Construct a general chronology (in 1000’s of years) for the core and draw a timescale up the side of your graph. Reconstruct palaeoclimate change represented by the oxygen isotope record (annotate the graph to show palaeoclimate extremes). E = Eccentricity of orbit T = Obliquity of the Ecliptic (tilt) P = Precession of the Equinoxes Source: FAQ 6.1. Fig 1. IPCC, 2007. Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change [Solomon, S., Qin, D., Manning, M., Chen, Z., Marquis, M., Avervt, K.B., Tignor, M. and Miller, H.L. (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, 996 pp.
13. Summary The origin of the ice ages remains a very controversial topic. There are two opposing theories that have implications for the origin of Quaternary ice ages. Both theories are in agreement that the Quaternary ice ages are a function of CO2 in the atmosphere and the Greenhouse Effect. Robert Berner believes that the ice ages are essentially a consequence of carbon storage mechanisms corresponding with a decrease in decarbonation. Maureen Raymoet al., however, argues that as the Himalayas grew, heavy monsoon rains combined with CO2 in the air eroded the newly exposed rock, removing so much CO2 out of the atmosphere that global temperatures dropped. In 1991, Eric Sundquist concluded that both theories have their place in nature, but operate over different timescales.
14. References Berner, R.A. 1990. Atmospheric carbon dioxide levels over Phanerozoic time. Science, 249: 1382-1386. Broecker, W.S. and Denton, G.H. 1990. What drives glacial cycles? Scientific American, 262(1): 48-56. Harris, S.A. 2002. Global heat budget, plate tectonics and climate change. GeografiskaAnnaler, A84: 1-9. Hays, J.D., Imbrie, J. and Shackleton, N.J. 1976. Variations in the earth’s orbit: pacemaker of the ice ages. Science, 194: 1121-1132. Molnar, P. and England, P. 1990. Late Cenozoic uplift of mountain-ranges and global climate change – chicken or egg? Nature, 346: 29-34. Paterson, D. 1993. Did Tibet cool the world? New Scientist, 2nd July issue, 29-33. Raymo, M.E. and Ruddiman, W.F. 1992. Tectonic forcing of late Cenozoic climate. Nature, 359: 117-122. Raymo, M.E., Ruddiman, W.F. and Froelich, P.N. 1988. Influence of late Cenozoic mountain building on ocean geochemical cycles. Geology, 16: 649-653. Ruddiman, W.F. and Kutzbach, J.E. 1991. Plateau uplift and climatic change. Scientific American, 264(3): 66-. Sundquist, E.T. 1991. Steady- and non-steady-state carbonate-silicate controls on atmospheric CO2. Quaternary Science Reviews, 10: 283-296.
15. This resource was created by the University of Wales, Newport and released as an open educational resource through the 'C-change in GEES' project exploring the open licensing of climate change and sustainability resources in the Geography, Earth and Environmental Sciences. The C-change in GEES project was funded by HEFCE as part of the JISC/HE Academy UKOER programme and coordinated by the GEES Subject Centre. This resource is licensed under the terms of the Attribution-Non-Commercial-Share Alike 2.0 UK: England & Wales license (http://creativecommons.org/licenses/by-nc-sa/2.0/uk/). All images courtesy of Professor Simon Haslett. However the resource, where specified below, contains other 3rd party materials under their own licenses. The licenses and attributions are outlined below: The name of the University of Wales, Newport and its logos are unregistered trade marks of the University. The University reserves all rights to these items beyond their inclusion in these CC resources. The JISC logo, the C-change logo and the logo of the Higher Education Academy Subject Centre for the Geography, Earth and Environmental Sciences are licensed under the terms of the Creative Commons Attribution -non-commercial-No Derivative Works 2.0 UK England & Wales license. All reproductions must comply with the terms of that license.
Editor's Notes
Steady-state – the notion that the input, output and properties of a system remain constant over time.Tectonic activity i.e. sea-floor spreading, subduction. Sea-floor spreading is the process where the ocean floor is extended when two plates move apart. These plates ultimately become bigger at the expense of other plates, which melt back into the earth in a process called subduction.