SlideShare une entreprise Scribd logo
1  sur  4
Télécharger pour lire hors ligne
Did England used to look like this?

Ice Ages are periods of Earth’s past when conditions were

much colder than today. Areas like Scotland were covered
with deep ice and sea-levels everywhere were lower. This was
because less water flowed into the sea from rivers once snow
and ice began to build up on the land.
Major past changes have taken place in the average temperature
of the Earth’s atmosphere. 100 million years ago at the time of
the dinosaurs, conditions were much hotter than today.
There have also been many cold phases called ice ages. Some
scientists believe that the coldest chapter of Planet Earth’s took
place 700 million years ago. They describe it as the “Snowball
earth” era.
Our last major cold period, the Pleistocene, started 1.8 million
years ago and ended just 10,000 years before the present day.
Since then, conditions have been warmer. This most recent
10,000 years is called the Holocene. The Pleistocene and the
Holocene are part of the Quaternary Period of Earth history.

Natural causes of climate change
The earth’s atmosphere is sometimes affected by naturally
occurring changes that can result in climate becoming colder or
warmer. Some changes take place over a short time-scale and
can explain decades or particular years of warming or cooling.
Other changes are far more significant and can last for
thousands, or even millions of years.
Below is a table that shows four suggestions about why natural
changes occur and temperatures get colder. Before you read any
further, take a guess as to which four are probably / possibly
true and try to spot the one which is definitely false.
Suggested explanation
The Earth’s orbit around the sun
changes shape so that the sun is
further away from us
Too much carbon dioxide is added
to the air which causes
temperatures to get colder
Some of the Earth’s mountains grow
too high, because of plate tectonic
movement!
The sun gets too spotty, with dark
spots appearing on its surface
Too many major volcanoes explode,
producing massive amounts of
smoke and ash

Possibly true or
definitely false?
Did you work out the one that is definitely false? If not, read on
and then go back and try again.
Different scientists have offered various explanations as to why
the Earth has sometimes got colder.
Orbit changes
Changes in how the Earth moves around the sun are believed to
cause Ice Ages. According to Milankovitch (a Serbian physicist),
every 100,000 years or so the Earth’s orbit changes from a
circular to egg-shaped pattern. This changes how much sunlight
we receive.
Solar output
The sun’s output is not constant. Cycles have been detected that
reduce or increase the amount of solar energy. The most wellknown phenomenon is sun spot activity, when uneven
temperatures develop on the sun’s surface. These can be seen as
tiny black spots on photographs of the sun taken by experts
(never try this yourself). Sunspots seem to come and go following
an irregular cycle that lasts about 11 years.
Volcanic activity
Major volcanic eruptions lead to a brief period of global cooling,
due to ash and dust particles being ejected high into the
atmosphere, blanketing the earth. The most recent explosion to
have a similar effect was Pinatubo (1991). Sunlight reaching
earth was reduced by 10%. World temperatures fell by nearly half
a degree in the following year.
The uplift of the Tibetan Plateau (home of the Himalayan
glaciers)
The earth’s continents move and occasionally collide with one
another (this is called plate tectonics). When India collided with
Asia, land was forced up to form the Himalayas. A complex series
of events followed that changed the earth’s climate and may
have caused cooling.
Activity

How much of Britain was
covered with ice during the
last Ice Age? For homework,
research this on the internet
and then draw your own line
on the map below showing
the maximum extent of the
ice.

Text © RGS-IBG/Simon Oakes 2009
Photo © http://www.flickr.com/photos/faisalsaeed/212339449/

Contenu connexe

Tendances

Climate System
Climate SystemClimate System
Climate SystemEd Stermer
 
The Evolution of Earth
The Evolution of EarthThe Evolution of Earth
The Evolution of EarthJigyasa Singh
 
Biogeo lec 7 glaciation and the pleistocene
Biogeo lec 7   glaciation and the pleistoceneBiogeo lec 7   glaciation and the pleistocene
Biogeo lec 7 glaciation and the pleistoceneMatt Robinson
 
Weather And Climate
Weather And ClimateWeather And Climate
Weather And Climatejdmcd
 
Earth's Climate
Earth's ClimateEarth's Climate
Earth's ClimateOhMiss
 
General Circulation of the Atmosphere
General Circulation of the AtmosphereGeneral Circulation of the Atmosphere
General Circulation of the AtmosphereKhalilur Rahman
 
Weather & climate 1
Weather & climate   1Weather & climate   1
Weather & climate 1pjb09138
 
Atmospheric circulation-Climatology Chapter
Atmospheric circulation-Climatology ChapterAtmospheric circulation-Climatology Chapter
Atmospheric circulation-Climatology ChapterKaium Chowdhury
 
weather and climate ppt for students..
weather and climate ppt for students..weather and climate ppt for students..
weather and climate ppt for students..Aditya Ghosh
 
The movements of the Earth
The movements of the Earth  The movements of the Earth
The movements of the Earth Mariadebiologia
 
Desert, types of desert, land forms, dunes and types of dunes
Desert, types of desert, land forms, dunes and types of dunesDesert, types of desert, land forms, dunes and types of dunes
Desert, types of desert, land forms, dunes and types of dunesTayyaba Arshad Arshad Mahmood
 
Layers of the Atmosphere
Layers of the AtmosphereLayers of the Atmosphere
Layers of the AtmosphereJan Parker
 
climate change in the past: Palaeoclimate
climate change in the past: Palaeoclimateclimate change in the past: Palaeoclimate
climate change in the past: Palaeoclimatecdenef
 
Structure Of The Earth
Structure Of The EarthStructure Of The Earth
Structure Of The Earthamr hassaan
 

Tendances (20)

Grade 5 weather
Grade 5 weatherGrade 5 weather
Grade 5 weather
 
Climate System
Climate SystemClimate System
Climate System
 
Air masses and fronts
Air masses and frontsAir masses and fronts
Air masses and fronts
 
Weather and Climate
Weather and ClimateWeather and Climate
Weather and Climate
 
Origin of earth
Origin of earthOrigin of earth
Origin of earth
 
The Evolution of Earth
The Evolution of EarthThe Evolution of Earth
The Evolution of Earth
 
Biogeo lec 7 glaciation and the pleistocene
Biogeo lec 7   glaciation and the pleistoceneBiogeo lec 7   glaciation and the pleistocene
Biogeo lec 7 glaciation and the pleistocene
 
Weather And Climate
Weather And ClimateWeather And Climate
Weather And Climate
 
Earth's Climate
Earth's ClimateEarth's Climate
Earth's Climate
 
General Circulation of the Atmosphere
General Circulation of the AtmosphereGeneral Circulation of the Atmosphere
General Circulation of the Atmosphere
 
Weather & climate 1
Weather & climate   1Weather & climate   1
Weather & climate 1
 
A. history of astronomy
A. history of astronomyA. history of astronomy
A. history of astronomy
 
Atmospheric circulation-Climatology Chapter
Atmospheric circulation-Climatology ChapterAtmospheric circulation-Climatology Chapter
Atmospheric circulation-Climatology Chapter
 
Weather vs climate
Weather vs climateWeather vs climate
Weather vs climate
 
weather and climate ppt for students..
weather and climate ppt for students..weather and climate ppt for students..
weather and climate ppt for students..
 
The movements of the Earth
The movements of the Earth  The movements of the Earth
The movements of the Earth
 
Desert, types of desert, land forms, dunes and types of dunes
Desert, types of desert, land forms, dunes and types of dunesDesert, types of desert, land forms, dunes and types of dunes
Desert, types of desert, land forms, dunes and types of dunes
 
Layers of the Atmosphere
Layers of the AtmosphereLayers of the Atmosphere
Layers of the Atmosphere
 
climate change in the past: Palaeoclimate
climate change in the past: Palaeoclimateclimate change in the past: Palaeoclimate
climate change in the past: Palaeoclimate
 
Structure Of The Earth
Structure Of The EarthStructure Of The Earth
Structure Of The Earth
 

En vedette (20)

Ice age powerpoint
Ice age powerpointIce age powerpoint
Ice age powerpoint
 
Ice Age
Ice AgeIce Age
Ice Age
 
Ice age
Ice ageIce age
Ice age
 
Ice age
Ice ageIce age
Ice age
 
Ice Age 3
Ice Age 3Ice Age 3
Ice Age 3
 
Glaciers
GlaciersGlaciers
Glaciers
 
The Little ice age
The Little ice ageThe Little ice age
The Little ice age
 
Ice Age: Collision Course
Ice Age: Collision CourseIce Age: Collision Course
Ice Age: Collision Course
 
Where is the Shoreline?
Where is the Shoreline?Where is the Shoreline?
Where is the Shoreline?
 
What are glaciers?
What are glaciers?What are glaciers?
What are glaciers?
 
Geology lecture 17
Geology lecture 17Geology lecture 17
Geology lecture 17
 
Climate & history little ice age
Climate & history little ice ageClimate & history little ice age
Climate & history little ice age
 
10 Facts You Need to Know About Childhood Cancer Awareness Month
10 Facts You Need to Know About Childhood Cancer Awareness Month10 Facts You Need to Know About Childhood Cancer Awareness Month
10 Facts You Need to Know About Childhood Cancer Awareness Month
 
Love, hate and other emotions
Love, hate and other emotionsLove, hate and other emotions
Love, hate and other emotions
 
Reasons to live
Reasons to liveReasons to live
Reasons to live
 
Music In My Life
Music In My LifeMusic In My Life
Music In My Life
 
Cancer Prevention
Cancer PreventionCancer Prevention
Cancer Prevention
 
Everest People
Everest PeopleEverest People
Everest People
 
Music is life
Music is lifeMusic is life
Music is life
 
Everest facts
Everest factsEverest facts
Everest facts
 

Similaire à What are ice ages?

The natural causes of climate change
The natural causes of climate changeThe natural causes of climate change
The natural causes of climate changeJoBlack
 
Science climate project
Science climate projectScience climate project
Science climate projectnashmiya
 
Science climate project
Science climate projectScience climate project
Science climate projectnashmiya
 
Lesson1 climate and change GCSE Edexcel B Geography
Lesson1 climate and change GCSE Edexcel B GeographyLesson1 climate and change GCSE Edexcel B Geography
Lesson1 climate and change GCSE Edexcel B Geographysarah marks
 
Geo pro
Geo proGeo pro
Geo projoremy
 
Climate: Climatic Change - Evidence, Cycles and The Future
Climate: Climatic Change - Evidence, Cycles and The FutureClimate: Climatic Change - Evidence, Cycles and The Future
Climate: Climatic Change - Evidence, Cycles and The Futuregeomillie
 
Climatesystem 100427220733-phpapp02
Climatesystem 100427220733-phpapp02Climatesystem 100427220733-phpapp02
Climatesystem 100427220733-phpapp02mjasdan
 
Millenial Scale For Climate Change
Millenial Scale For Climate ChangeMillenial Scale For Climate Change
Millenial Scale For Climate ChangeSundas Waheed
 
Long term & short term effects of climate 2
Long term & short term effects of climate 2Long term & short term effects of climate 2
Long term & short term effects of climate 2Sarah Ramanathan
 
Past Climate Change
Past Climate ChangePast Climate Change
Past Climate ChangeJoBlack
 
5. What Is The Evidence For Global Warming Nsr
5. What Is The Evidence For Global Warming   Nsr5. What Is The Evidence For Global Warming   Nsr
5. What Is The Evidence For Global Warming Nsrtudorgeog
 
Causes Of The Greenhouse Effect
Causes Of The Greenhouse EffectCauses Of The Greenhouse Effect
Causes Of The Greenhouse EffectJosephine Romero
 
Climate change and its effects
Climate change and  its effects Climate change and  its effects
Climate change and its effects Sakil Ahmed
 
Long term & short term effects of climate
Long term & short term effects of climateLong term & short term effects of climate
Long term & short term effects of climateSarah Ramanathan
 
Presentation1
Presentation1Presentation1
Presentation1khayat83
 

Similaire à What are ice ages? (20)

The natural causes of climate change
The natural causes of climate changeThe natural causes of climate change
The natural causes of climate change
 
Science climate project
Science climate projectScience climate project
Science climate project
 
Science climate project
Science climate projectScience climate project
Science climate project
 
Lesson1 climate and change GCSE Edexcel B Geography
Lesson1 climate and change GCSE Edexcel B GeographyLesson1 climate and change GCSE Edexcel B Geography
Lesson1 climate and change GCSE Edexcel B Geography
 
task A
task Atask A
task A
 
Geo pro
Geo proGeo pro
Geo pro
 
Climate: Climatic Change - Evidence, Cycles and The Future
Climate: Climatic Change - Evidence, Cycles and The FutureClimate: Climatic Change - Evidence, Cycles and The Future
Climate: Climatic Change - Evidence, Cycles and The Future
 
Climatesystem 100427220733-phpapp02
Climatesystem 100427220733-phpapp02Climatesystem 100427220733-phpapp02
Climatesystem 100427220733-phpapp02
 
Millenial Scale For Climate Change
Millenial Scale For Climate ChangeMillenial Scale For Climate Change
Millenial Scale For Climate Change
 
Millinial Scale
Millinial ScaleMillinial Scale
Millinial Scale
 
Long term & short term effects of climate 2
Long term & short term effects of climate 2Long term & short term effects of climate 2
Long term & short term effects of climate 2
 
Past Climate Change
Past Climate ChangePast Climate Change
Past Climate Change
 
3sec1
3sec13sec1
3sec1
 
5. What Is The Evidence For Global Warming Nsr
5. What Is The Evidence For Global Warming   Nsr5. What Is The Evidence For Global Warming   Nsr
5. What Is The Evidence For Global Warming Nsr
 
Hansen
HansenHansen
Hansen
 
Global warming
Global warmingGlobal warming
Global warming
 
Causes Of The Greenhouse Effect
Causes Of The Greenhouse EffectCauses Of The Greenhouse Effect
Causes Of The Greenhouse Effect
 
Climate change and its effects
Climate change and  its effects Climate change and  its effects
Climate change and its effects
 
Long term & short term effects of climate
Long term & short term effects of climateLong term & short term effects of climate
Long term & short term effects of climate
 
Presentation1
Presentation1Presentation1
Presentation1
 

Plus de Bourne Grammar School (18)

River Tees
River TeesRiver Tees
River Tees
 
What are periglacial processes?
What are periglacial processes?What are periglacial processes?
What are periglacial processes?
 
What are fluvioglacial processes?
What are fluvioglacial processes?What are fluvioglacial processes?
What are fluvioglacial processes?
 
Glacial transportation and deposition
Glacial transportation and depositionGlacial transportation and deposition
Glacial transportation and deposition
 
Representing place 2
Representing place 2Representing place 2
Representing place 2
 
Glacial erosion and weathering
Glacial erosion and weatheringGlacial erosion and weathering
Glacial erosion and weathering
 
Management of the River Tees
Management of the River TeesManagement of the River Tees
Management of the River Tees
 
Water aid in mali plan 2010 2015
Water aid in mali plan 2010 2015Water aid in mali plan 2010 2015
Water aid in mali plan 2010 2015
 
East Cornwall CFMP
East Cornwall CFMPEast Cornwall CFMP
East Cornwall CFMP
 
Boscastle flood summary
Boscastle flood summaryBoscastle flood summary
Boscastle flood summary
 
Boscastle flood timeline
Boscastle flood timelineBoscastle flood timeline
Boscastle flood timeline
 
Boscastle flood North Cornwall Council
Boscastle flood North Cornwall CouncilBoscastle flood North Cornwall Council
Boscastle flood North Cornwall Council
 
Climate Change: Effects on the UK
Climate Change: Effects on the UKClimate Change: Effects on the UK
Climate Change: Effects on the UK
 
The Humber Estuary and Holderness Coast
The Humber Estuary and Holderness CoastThe Humber Estuary and Holderness Coast
The Humber Estuary and Holderness Coast
 
Coastal Processes on the Holderness Coast
Coastal Processes on the Holderness CoastCoastal Processes on the Holderness Coast
Coastal Processes on the Holderness Coast
 
Ate urban climatology
Ate urban climatologyAte urban climatology
Ate urban climatology
 
Urban heat island and air quality of london
Urban heat island and air quality of londonUrban heat island and air quality of london
Urban heat island and air quality of london
 
Met Office - Microclimate
Met Office - MicroclimateMet Office - Microclimate
Met Office - Microclimate
 

Dernier

Crea il tuo assistente AI con lo Stregatto (open source python framework)
Crea il tuo assistente AI con lo Stregatto (open source python framework)Crea il tuo assistente AI con lo Stregatto (open source python framework)
Crea il tuo assistente AI con lo Stregatto (open source python framework)Commit University
 
UiPath Solutions Management Preview - Northern CA Chapter - March 22.pdf
UiPath Solutions Management Preview - Northern CA Chapter - March 22.pdfUiPath Solutions Management Preview - Northern CA Chapter - March 22.pdf
UiPath Solutions Management Preview - Northern CA Chapter - March 22.pdfDianaGray10
 
IESVE Software for Florida Code Compliance Using ASHRAE 90.1-2019
IESVE Software for Florida Code Compliance Using ASHRAE 90.1-2019IESVE Software for Florida Code Compliance Using ASHRAE 90.1-2019
IESVE Software for Florida Code Compliance Using ASHRAE 90.1-2019IES VE
 
VoIP Service and Marketing using Odoo and Asterisk PBX
VoIP Service and Marketing using Odoo and Asterisk PBXVoIP Service and Marketing using Odoo and Asterisk PBX
VoIP Service and Marketing using Odoo and Asterisk PBXTarek Kalaji
 
9 Steps For Building Winning Founding Team
9 Steps For Building Winning Founding Team9 Steps For Building Winning Founding Team
9 Steps For Building Winning Founding TeamAdam Moalla
 
NIST Cybersecurity Framework (CSF) 2.0 Workshop
NIST Cybersecurity Framework (CSF) 2.0 WorkshopNIST Cybersecurity Framework (CSF) 2.0 Workshop
NIST Cybersecurity Framework (CSF) 2.0 WorkshopBachir Benyammi
 
AI You Can Trust - Ensuring Success with Data Integrity Webinar
AI You Can Trust - Ensuring Success with Data Integrity WebinarAI You Can Trust - Ensuring Success with Data Integrity Webinar
AI You Can Trust - Ensuring Success with Data Integrity WebinarPrecisely
 
UiPath Studio Web workshop series - Day 7
UiPath Studio Web workshop series - Day 7UiPath Studio Web workshop series - Day 7
UiPath Studio Web workshop series - Day 7DianaGray10
 
AI Fame Rush Review – Virtual Influencer Creation In Just Minutes
AI Fame Rush Review – Virtual Influencer Creation In Just MinutesAI Fame Rush Review – Virtual Influencer Creation In Just Minutes
AI Fame Rush Review – Virtual Influencer Creation In Just MinutesMd Hossain Ali
 
Bird eye's view on Camunda open source ecosystem
Bird eye's view on Camunda open source ecosystemBird eye's view on Camunda open source ecosystem
Bird eye's view on Camunda open source ecosystemAsko Soukka
 
COMPUTER 10 Lesson 8 - Building a Website
COMPUTER 10 Lesson 8 - Building a WebsiteCOMPUTER 10 Lesson 8 - Building a Website
COMPUTER 10 Lesson 8 - Building a Websitedgelyza
 
ADOPTING WEB 3 FOR YOUR BUSINESS: A STEP-BY-STEP GUIDE
ADOPTING WEB 3 FOR YOUR BUSINESS: A STEP-BY-STEP GUIDEADOPTING WEB 3 FOR YOUR BUSINESS: A STEP-BY-STEP GUIDE
ADOPTING WEB 3 FOR YOUR BUSINESS: A STEP-BY-STEP GUIDELiveplex
 
UiPath Community: AI for UiPath Automation Developers
UiPath Community: AI for UiPath Automation DevelopersUiPath Community: AI for UiPath Automation Developers
UiPath Community: AI for UiPath Automation DevelopersUiPathCommunity
 
Linked Data in Production: Moving Beyond Ontologies
Linked Data in Production: Moving Beyond OntologiesLinked Data in Production: Moving Beyond Ontologies
Linked Data in Production: Moving Beyond OntologiesDavid Newbury
 
How Accurate are Carbon Emissions Projections?
How Accurate are Carbon Emissions Projections?How Accurate are Carbon Emissions Projections?
How Accurate are Carbon Emissions Projections?IES VE
 
Machine Learning Model Validation (Aijun Zhang 2024).pdf
Machine Learning Model Validation (Aijun Zhang 2024).pdfMachine Learning Model Validation (Aijun Zhang 2024).pdf
Machine Learning Model Validation (Aijun Zhang 2024).pdfAijun Zhang
 
KubeConEU24-Monitoring Kubernetes and Cloud Spend with OpenCost
KubeConEU24-Monitoring Kubernetes and Cloud Spend with OpenCostKubeConEU24-Monitoring Kubernetes and Cloud Spend with OpenCost
KubeConEU24-Monitoring Kubernetes and Cloud Spend with OpenCostMatt Ray
 
Basic Building Blocks of Internet of Things.
Basic Building Blocks of Internet of Things.Basic Building Blocks of Internet of Things.
Basic Building Blocks of Internet of Things.YounusS2
 
Anypoint Code Builder , Google Pub sub connector and MuleSoft RPA
Anypoint Code Builder , Google Pub sub connector and MuleSoft RPAAnypoint Code Builder , Google Pub sub connector and MuleSoft RPA
Anypoint Code Builder , Google Pub sub connector and MuleSoft RPAshyamraj55
 

Dernier (20)

Crea il tuo assistente AI con lo Stregatto (open source python framework)
Crea il tuo assistente AI con lo Stregatto (open source python framework)Crea il tuo assistente AI con lo Stregatto (open source python framework)
Crea il tuo assistente AI con lo Stregatto (open source python framework)
 
UiPath Solutions Management Preview - Northern CA Chapter - March 22.pdf
UiPath Solutions Management Preview - Northern CA Chapter - March 22.pdfUiPath Solutions Management Preview - Northern CA Chapter - March 22.pdf
UiPath Solutions Management Preview - Northern CA Chapter - March 22.pdf
 
IESVE Software for Florida Code Compliance Using ASHRAE 90.1-2019
IESVE Software for Florida Code Compliance Using ASHRAE 90.1-2019IESVE Software for Florida Code Compliance Using ASHRAE 90.1-2019
IESVE Software for Florida Code Compliance Using ASHRAE 90.1-2019
 
VoIP Service and Marketing using Odoo and Asterisk PBX
VoIP Service and Marketing using Odoo and Asterisk PBXVoIP Service and Marketing using Odoo and Asterisk PBX
VoIP Service and Marketing using Odoo and Asterisk PBX
 
9 Steps For Building Winning Founding Team
9 Steps For Building Winning Founding Team9 Steps For Building Winning Founding Team
9 Steps For Building Winning Founding Team
 
NIST Cybersecurity Framework (CSF) 2.0 Workshop
NIST Cybersecurity Framework (CSF) 2.0 WorkshopNIST Cybersecurity Framework (CSF) 2.0 Workshop
NIST Cybersecurity Framework (CSF) 2.0 Workshop
 
AI You Can Trust - Ensuring Success with Data Integrity Webinar
AI You Can Trust - Ensuring Success with Data Integrity WebinarAI You Can Trust - Ensuring Success with Data Integrity Webinar
AI You Can Trust - Ensuring Success with Data Integrity Webinar
 
UiPath Studio Web workshop series - Day 7
UiPath Studio Web workshop series - Day 7UiPath Studio Web workshop series - Day 7
UiPath Studio Web workshop series - Day 7
 
AI Fame Rush Review – Virtual Influencer Creation In Just Minutes
AI Fame Rush Review – Virtual Influencer Creation In Just MinutesAI Fame Rush Review – Virtual Influencer Creation In Just Minutes
AI Fame Rush Review – Virtual Influencer Creation In Just Minutes
 
Bird eye's view on Camunda open source ecosystem
Bird eye's view on Camunda open source ecosystemBird eye's view on Camunda open source ecosystem
Bird eye's view on Camunda open source ecosystem
 
COMPUTER 10 Lesson 8 - Building a Website
COMPUTER 10 Lesson 8 - Building a WebsiteCOMPUTER 10 Lesson 8 - Building a Website
COMPUTER 10 Lesson 8 - Building a Website
 
ADOPTING WEB 3 FOR YOUR BUSINESS: A STEP-BY-STEP GUIDE
ADOPTING WEB 3 FOR YOUR BUSINESS: A STEP-BY-STEP GUIDEADOPTING WEB 3 FOR YOUR BUSINESS: A STEP-BY-STEP GUIDE
ADOPTING WEB 3 FOR YOUR BUSINESS: A STEP-BY-STEP GUIDE
 
UiPath Community: AI for UiPath Automation Developers
UiPath Community: AI for UiPath Automation DevelopersUiPath Community: AI for UiPath Automation Developers
UiPath Community: AI for UiPath Automation Developers
 
Linked Data in Production: Moving Beyond Ontologies
Linked Data in Production: Moving Beyond OntologiesLinked Data in Production: Moving Beyond Ontologies
Linked Data in Production: Moving Beyond Ontologies
 
How Accurate are Carbon Emissions Projections?
How Accurate are Carbon Emissions Projections?How Accurate are Carbon Emissions Projections?
How Accurate are Carbon Emissions Projections?
 
Machine Learning Model Validation (Aijun Zhang 2024).pdf
Machine Learning Model Validation (Aijun Zhang 2024).pdfMachine Learning Model Validation (Aijun Zhang 2024).pdf
Machine Learning Model Validation (Aijun Zhang 2024).pdf
 
201610817 - edge part1
201610817 - edge part1201610817 - edge part1
201610817 - edge part1
 
KubeConEU24-Monitoring Kubernetes and Cloud Spend with OpenCost
KubeConEU24-Monitoring Kubernetes and Cloud Spend with OpenCostKubeConEU24-Monitoring Kubernetes and Cloud Spend with OpenCost
KubeConEU24-Monitoring Kubernetes and Cloud Spend with OpenCost
 
Basic Building Blocks of Internet of Things.
Basic Building Blocks of Internet of Things.Basic Building Blocks of Internet of Things.
Basic Building Blocks of Internet of Things.
 
Anypoint Code Builder , Google Pub sub connector and MuleSoft RPA
Anypoint Code Builder , Google Pub sub connector and MuleSoft RPAAnypoint Code Builder , Google Pub sub connector and MuleSoft RPA
Anypoint Code Builder , Google Pub sub connector and MuleSoft RPA
 

What are ice ages?

  • 1. Did England used to look like this? Ice Ages are periods of Earth’s past when conditions were much colder than today. Areas like Scotland were covered with deep ice and sea-levels everywhere were lower. This was because less water flowed into the sea from rivers once snow and ice began to build up on the land. Major past changes have taken place in the average temperature of the Earth’s atmosphere. 100 million years ago at the time of the dinosaurs, conditions were much hotter than today. There have also been many cold phases called ice ages. Some scientists believe that the coldest chapter of Planet Earth’s took place 700 million years ago. They describe it as the “Snowball earth” era.
  • 2. Our last major cold period, the Pleistocene, started 1.8 million years ago and ended just 10,000 years before the present day. Since then, conditions have been warmer. This most recent 10,000 years is called the Holocene. The Pleistocene and the Holocene are part of the Quaternary Period of Earth history. Natural causes of climate change The earth’s atmosphere is sometimes affected by naturally occurring changes that can result in climate becoming colder or warmer. Some changes take place over a short time-scale and can explain decades or particular years of warming or cooling. Other changes are far more significant and can last for thousands, or even millions of years. Below is a table that shows four suggestions about why natural changes occur and temperatures get colder. Before you read any further, take a guess as to which four are probably / possibly true and try to spot the one which is definitely false. Suggested explanation The Earth’s orbit around the sun changes shape so that the sun is further away from us Too much carbon dioxide is added to the air which causes temperatures to get colder Some of the Earth’s mountains grow too high, because of plate tectonic movement! The sun gets too spotty, with dark spots appearing on its surface Too many major volcanoes explode, producing massive amounts of smoke and ash Possibly true or definitely false?
  • 3. Did you work out the one that is definitely false? If not, read on and then go back and try again. Different scientists have offered various explanations as to why the Earth has sometimes got colder. Orbit changes Changes in how the Earth moves around the sun are believed to cause Ice Ages. According to Milankovitch (a Serbian physicist), every 100,000 years or so the Earth’s orbit changes from a circular to egg-shaped pattern. This changes how much sunlight we receive. Solar output The sun’s output is not constant. Cycles have been detected that reduce or increase the amount of solar energy. The most wellknown phenomenon is sun spot activity, when uneven temperatures develop on the sun’s surface. These can be seen as tiny black spots on photographs of the sun taken by experts (never try this yourself). Sunspots seem to come and go following an irregular cycle that lasts about 11 years. Volcanic activity Major volcanic eruptions lead to a brief period of global cooling, due to ash and dust particles being ejected high into the atmosphere, blanketing the earth. The most recent explosion to have a similar effect was Pinatubo (1991). Sunlight reaching earth was reduced by 10%. World temperatures fell by nearly half a degree in the following year. The uplift of the Tibetan Plateau (home of the Himalayan glaciers) The earth’s continents move and occasionally collide with one another (this is called plate tectonics). When India collided with Asia, land was forced up to form the Himalayas. A complex series of events followed that changed the earth’s climate and may have caused cooling.
  • 4. Activity How much of Britain was covered with ice during the last Ice Age? For homework, research this on the internet and then draw your own line on the map below showing the maximum extent of the ice. Text © RGS-IBG/Simon Oakes 2009 Photo © http://www.flickr.com/photos/faisalsaeed/212339449/