Unit 6 Weather and Climate

what are the three sources of anthropogenic greenhouse gases?

carbon dioxide

methane

nitrous oxide

what % of anthropogenic global warming is CO2 responsible for?

85%

approximately what % of methane emissions come from human activities?

60% from activities such as cattle breeding, rice agriculture and fossil fuel exploitation

What causes nitrous oxides in the air?

biomass burning

fertilizer use

industrial processes

GLOBAL TEMPERATURE INCREASES:

what is the global average temperature?

The global average temperature is now 1 degree warmer

which areas are warming more rapidly than others?

Polar regions and Arctic areas.

why have these areas experienced rapid temperature increases?

due to melting of sea ice and thermal expansion of water which causes the area to warm even faster

IMPACT OF ANTHROPOGENIC CLIMATE CHANGE ON SHIFTING CLIMATE BELTS:

what does climate in different regions lead to the formation of?

large scale ecosystems or biomes

which biomes are particularly susceptible from global warming?

Tundras

THE ARCTIC TUNDRA BIOME AND CLIMATE CHANGE:

Arctic ocean warming and sea ice: by how much have the surface waters of the Arctic Ocean warmed by and was has this led to in relation to sea ice?

0.5 degrees which along with the change in temperature has led to a decline in Arctic Sea Ice

summarise the decline in September sea ice cover between 1981 and 2010?

since 1981, there have been fluctuating within a steady decline in sea ice cover. From between 1992-2000 there has been a sharp decrease in the sea ice cover (7km to 4km)

IMPACT ON TUNDRA SPECIES:

how does arctic climate change impact polar bears?

• polar officially listed as threatened under the U.S. Endangered Species Act in 2008.

• polar bears require sea ice upon which to hunt for seals. As sea ice has declined so has polar bear numbers

• rising temps cause the sea ice to melt earlier in the year- this drives the bears to shore before they have built up enough fat reserves for the summer, leading to decreased survival rates.

• reduction of sea ice cover forces bears to swim for longer distances which depletes their energy stores and occasioanlly leading to drowning

how does arctic climate change lead to biome shifts?

Ecological society of America estimate that by 2100, 77% of the tundra biome in Alaska will have disappeared because of global warming as pine forests will shift nowrthwards up to 500km and replace the tundra

what is the impact of arctic climate change on the caribou?

• affected by the shift in the tundra as they feed on tundra mosses. As forest spreads north their feeding grounds are disappearing.

• overall, the caribou are declining at rapid rates in North West Canada

TIPPING POINTS FROM CLIMATE CHANGE IN THE ARCTIC:

what is a climate tipping point?

• is a crittical threshold when global or regional climate changes from one stable state to another stable state.

• tipping point may or may not be reversible

MAIN CLIMATE TIPPING POINTS IN THE ARCTIC?

1. ocean current changes

• cold, salty, deep water is produced in the North atlantic as the North Atlantic Drift flows northwards

• however, when ice sheets such as the Greenland Ice Sheet melt, they release freshwater into the Atlantic. An input of freshwater makes the ocean less salty and less dense, slowing down ocean circulation and causing the sinking of this current to occur further south

what is the potential impact of this tipping point?

• this could mean that areas such as the UK could possibly not see warming of its climate and could lead to very cold winters and summers e.g. The Little Ice Age

2. Ice Albedo Feedback Mechanism

• once sea ice cover has melted, sea ice is replaced by darker ocean which has a lower albedo (reflectivity) and absorbs insolation thus warming the ocean more quickly

• this is a positive feedback loop

3. Methane Release

• potent greenhouse gas that is 23x more potent that CO2

METHANE AND CO2 IN PERMAFROST

• The permafrost contains vast amounts of frozen organic material

• when permafrost thaws, the frozen organic matter will thaw out and begin to decay

• as organic matter decays, it gets digested by microbes who release methane and CO2 as waste

• if there is no oxygen vailable, the microbes make methane

• most of the places where methane would form are wetlands and there are many miles of wetlands in the Arctic.

what are methane hydrates?

• Stored organic deposits within the sub sea permafrost on the Arctic continental shelf

• as the Arctic Ocean wamrs the sub sea permafrost thaws which in turn releases methane

• both of these sources of methane create another tipping point

Economic consequences of Arctic Tipping Points

what are the potential negative economic impacts of climate change n Arctic regions?

• changes in agriculture can impact agricultural production

• comapnies have to pay or internalise the externality of pollution

are there any pitential positive economic impacts of warming in the Arctic?

• warming in the arctic can lead to resources e.g oil and gas becoming more accessible.

• countries can exploit this leading to positive economic impacts

CLIMATE CHANGE & TIPPING POINTS IN TROPICAL RAINFOREST:

what is the importance of the Amazon in the Carbon Cycle?

• one of the Earth’s largest reservoirs of carbon dioxide

• helps regulate the global climate through the sequestration and storage of carbon dioxide in the biomass and soil

importance of Amazon in the Water Cycle?

• rainforests are the source of one-fifth of all fresh water on the planet

• amazon Basin’s hydrological system helps regulate the global and regional climate

• water condensation, evaporation and transpiration over the Amazon are key drivers of the global atmospheric circulation, affecting rainfall across South America and much of the Northern Hemisphere

Deforestation and the Amazon Tipping Point?

The World Bank estimated that the tipping point for the amazon could be approx 20% deforestation-currently 18% has been deforested

TIPPING POINT:

• Due to warmer global temps and deforestation, the Amazon becomes drier due to less water available in the atmosphere

• this leads to droughts occuring due to lack of rainfall

• this can lead to wildifres occuring which means more trees die and decompose or burn releasing CO2

• fewer trees means less water is returned to the atmosphere through evapotranspiration

• this leads to a decrease in rainfall

what was the Amazon dieback event of 2010?

• affected a 60% wider area than the 2005 severe dorught

• estimated that 8 billion tonnes of CO2 were to be released excluding CO2 released from forest fires

• killed in the low billions of trees

Update 2019: Amazon Burning

summarise the vents of 2019

• 7746 fires in Brazil

• 84% increase in the fires in 2019 since 2018

• respiratory diseases were rife leading to full hospitals

• burning detected inside indigenous lands and nature reserves

• dry season extending into critical moments

what is the economic cost of Amazon Tipping Point?

The estimated cumulative regional cost by 2050 of an Amazon tipping point would be $256.6 billion in GDP

STRATEGIES TO MITIGATE AND ADAPT TO CLIMATE CHANGE?

why we need to manage climate change?

if climate tipping points are reached the concept of runaway climate change may occur

what could happen if runaway climate change occurs?

• areas on the planet left uninhabitable e.g. The Maldives

• Amazon rainforest turning into a dry grassland

• more extreme weather

• tipping points reached

to what extent is it possible to stop climatic tipping points and runaway climate change?

• requires global action, it requires dramatic changes in people’s lifestyle HOWEVER, democratic societies people won’t vote for parties with strict environmental policies

CLIMATE MANAGEMENT STRATEGIES:

what variety of scales need to be applied?

1. international level

2. national level

3. individual

why might it be difficult to achieve a global agreement on controlling greenhouse gas emissions?

• some countries produce a lot of greenhouse gas per capita but not as much in total e.g. Australia produces a lot of per capita but not in total

• USA, however, pollutes a lot per person, in total and over time

Government strategies: The International Level

The United Nations Climate Change Conference is now an annual event

when were they first held?

in 1995

what happens in these meetings?

where global leaders have tried to agree global united strategies to address climate change.

Examples of these meetings can include?

1. The Kyoto Protocol-1997

2. The UN Paris Climate Conference 2015 and UN Net-Zero coalition

3. COP 26 Glasgow 2021

The Kyoto Protocol- what was it?

• was the first legally binding international agreement to reduce global greenhouse gases.

The Kyoto Protocol?

key information?

• the agreement by 168 countries came into force in Feb 2005

• AIM was to cut global emissions of greenhouse gas emissins by 55% by 2012 compared to 1990 levels

what were the terms under the agreement?

• industrialised countries will each reduce their emissions of greenhouse gases by at least 5.2%, the UK’s target was 12.5%

• it was agreed that historical and per capita emissions in developing countries are still relatively low. Therefire, developing countries will continue grow to meet their social and development needs.

HOWEVER,

many of the world’s nations has no formal starget set for emissions reduction

EVAL- Was the Kyoto Protocol a success?

SUCCESSES:

• The Kyoto Protocol was the first major global agremeent in which time bound targets were set to reduce greenhouse gases

FAILINGS:

• In 2001, President Clinton of USA who had attended the Kyoto meetings, was replaced with President Bush, who did not consent to the agreement.

• Therefore, the USA, the single largest producer of CO2 in 1997 and responsible for 25% of global emissions, has refused to adhere to any reduction target

• Newly industrialising and highly populated countries such as India and China were set no yargets for CO2 reductions. Since 1997 China’s CO"2 emissions have more than doubled, and it is now the world’s single largest emitter of CO2

eval 2: overall was the Kyoto Protocol successful in reducing emissions?

No.

what was the agreement of the UN Paris Climate Conference?

• is to set a goal of limiting global warming to 1.5 degrees compared to industrial levels

• to limit anthropogenic greenhosue gas emissions to the same level that the environment can absorb naturally, beginning at some point between 2050 and 2100

The UN Paris Climate Conference- Dec 2015

what are the successes?

• the Paris Agreement was signed by the 195 countries attending

• the agreement would become legally binding for over 50 countries which together represent at least 55% of global emissions

what were the failings of the agreement?

Trump got elected and pulled out of the Paris Agreement

UN Net Zero Coalition- a consequence of Paris 2015

why is questionable that the UK will reach this target?

• Finance, aviation or foreign imports are not included in our emissions calculations

• unlikely to hit net zero as foreign imports are liekly to increase.

• The idea of global shift is not equated into this calculation.

• If this emissions are not calculated in future, we could outsource our carbon emissions in future

COP 26 Glasgow 2021

what were the failings and limitations of this conference?

• despite the pleddgings made, global warming is on the track to be even higher

• China and India refused to sign up to the agremeent and refused to reduce their coal usage and consumption. Agreement had to be rewritten to allow for this. (this is a limitation as China and India are the most polluting)

COP 28 UAE 2023

why was COP 28 criticised?

• UAE is a country whose economy is heavily dependent on oil, is hosting COP 28

• The president of the meeting is an oil executive

• The president claimed that there is no evidence to support the claim that fossil fuels are causing climate change

• Saudi Arabia won’t even agree to phase out fossil fuels

• No agremeent was reached

• companies were using the conference to strike oil deals

Discuss and evaluate how effective are the COP meetings at addressing climate change?

• Gloabl temperatures are still going up

• in the last couple of years have started to accelerate.

• in 2024, global temps were >1.5 degrees for the first time

• climate conferences started really well, but as time went on, countries have been putting their economic needs first and pulling out of agreements to protect their economic interests

• Paris agreement was quite effective, yet the failings of the COP meetings overshadow the benefits and successes of the meetings.

2. GOVERNMENT STRATEGIES: The National Level In UK

what is the UK actually doing to achieve our Net Zero pledge by 2050?

• target is being achieved through a series of measures focusing on different sources of greenhouse gases such as transport, renewable energy strategies and land use policies

TRANSPORT STRATEGIES:

what has the UK done to reduce greenhouse gases?

• ban on selling new petrol, diesel or hybrid cars in the UK will be brought forward to 2035

• people will only be able to buy electric or hydrogen cars and vans once the ban comes into effect

what have other national government’s done?

(PARIS)

• introducing low emission zones and banning more polluting, older vehicles from central areas during weekdays

• car free initiatives

• construction of over 1,000km of bike lanes

what have other national government’s done?

(COMPENHAGEN)

• cycling infrastructure and ‘superhighways’

• public transport investment e.g. investing in electric buses and metro lines

ENERGY STRATEGIES?

currently, what % of all UK energy comes from renewablle sources?

About 50% of all UK energy comes from renewable sources.

what is the UK’s target of renewable energy % by 2035?

The UK's target is to reach 70% of its energy from renewable sources by 2035.

how has the UK’s energy mix changed?

energy mix has shifted significantly towards renewables, with a substantial decrease in coal use and an increase in wind and solar energy

susmmarise the growth in renewable wind energy?

the rise of offshore wind has been steadily increasing from a few hundred megawatts in the early 2000s to over 31,000 gigawatt hours

what is an example of a wind energy scheme in the UK?

• The Hornsea Project, exemplifies a significant wind energy scheme in the UK.

• Contracts for Difference scheme incentivises the development of renewable energy projects including wind farms

LAND USE POLICIES:

JAN 2020: Commission for Climate Change Land Use Policy for Net-Zero: Peatlands

how will this help manage climate change?

• restoring at least 50% of upland peat and 25% of lowland peat

• restoring peatland will help manage climate change as it will increase the amount of of carbon that is absorbed, taking more carbon out of the soil.

3. ACTIONS BY INDIVIDUALS

what can individuals do?

they can reduce their carbon footprint

how can individuals reduce their carbon footprint in the home?

• energy effiecient appliances

• smart metres

• solar panels

• heat pumps

how can individuals reduce their carbon footprint by transport?

• using public transport

• walking/cycling

• car sharing

• using electric vehicles

how can individuals reduce their carbon footprint when out shopping?

• Avoiding fast disposable fashion

• locally produced goods

• organic food

• eating/ shopping for less red meat

2. carbon offset

how does carbon offsetting work?

• a process that allows individuals, companies, or governments to compensate for their carbon dioxide (CO2) emissions by funding projects that reduce or remove an equivalent amount of greenhouse gases from the atmosphere. It balances out the carbon that they use.

3. Joining an environmental pressure group

e.g. GREENPEACE

What are a variety of things you can do if involved with greenpeace?

• signing a petition to the government to demand ocean protection

• give a donation to help combat destruction in the Amazon

• include a greenpeace donation in your will

• become a greenpeace volunteer

eval- are environmental groups successful?

JUST STOP OIL- March 2025 stopped protests as UK government announced they wouldnt issue any new liscences for oil and gas drilling in its waters

can be said to be successful

to what extent are the climate strategies working?

• the concentration of CO2 is increasing at an increasing rate (in 1990 ppm was 360 and in 2020 its greater than 400 ppm)

• the recent upturn of global methane emissions could be evidence of arctic amplification and permafrost degradation

• global temps are increasing but since 1980 temps are rapidly increasing.

therefore, it can be said that most of the climate strategies aren’t working and in future, if climate change is not mitigated, then it may be necessary for nations to adapt to climate change rather than mitigate.

ESSAY PLAN- TO WHAT EXTENT is it possible to mitigate the consequences of climatic tipping points? (INTRO)

INTRODUCTION:

Define climatic tipping point- a point at which a change in the climate system leads to significant and irreversible changes in the environment

• identify what causes the tipping point (>.15 degrees)

• identify tipping points: methane permafrost feedback loop, ice albedo feedback loop, change in ocean currents

• identify that negative consequences require mitigation to reduce mitigation

ESSAY PLAN- TO WHAT EXTENT is it possible to mitigate the consequences of climatic tipping points? MAIN BODY

MAIN BODY:

• Discuss various climatic tipping points, their potential impacts

• discuss that the way to mitigate these consequences is through effective management of climate change

summarise mitigation strategies and evaluate their successes in order to mitigate climate change

• international- climate conferences

• national- transport strategies, land use polciies and energy strategies, to what extent are these actions mitigating climate change

• individual- how can individuals help combat climate change (joining environmental groups, carbon offsetting, and lifestyle changes)

EVALUATE- to what extent have these staretgies worked- to do this compare them against data of climatic changes in recent years (yes they are successful as…/ no they have limitations as temps increased.. and give evidence so 2024 was the hottest year, methane emissions rapidly rising)

HOWEVER, IF these strategies arent working then the only things we can do is to ADAPT to living like this. HOW?

• low lying islands- have to adapt by building sea walls or they have to migrate (e.g. Male, in the Maldives)

• Agricultural adaptations- making crops more drought resistant and water efficient by genetically modifying crops) or by gowing salt-tolerant crops in Bangladesh to cope with increasing floods from cyclones in the area

ESSAY PLAN- TO WHAT EXTENT is it possible to mitigate the consequences of climatic tipping points? (CONCLUSION)

• mention that anthropogenic climate change is the key driver behind this

• mention that for the strategies to work they need to reduce climate change to <1.5

• as of yet this is not happening (give evidence e.g. concentration of Co2 is increasing at a rapid pace and is now at over 400ppm

• so it seems that adaptation is the future for populations if they want to manage climate change