Climate Change in the Geological Past

Climate Change in the Geological Past

• The Earth is in an ice age but experiencing global warming.
• Natural processes like volcanic activity release methane, ash, carbon monoxide and CO2, leading to rapid warming.
• El Nino involves warming in the eastern equatorial Pacific, linked to the cessation of nutrient-rich cold water upwelling off the coast of Peru.
• La Nina cools the eastern equatorial Pacific, and they both cause noticeable changes in global climate.
• These El Nino and La Nina cycles last 9-12 months, alternating between the two.
• The Milankovitch cycles includes precession, obliquity, and eccentricity
• Precession changes the direction of Earth's axis every 26,000 years.
• Obliquity, the tilt of Earth's, occurs every 40,000 years, impacts seasonal differences.
• Eccentricity (the shape of Earth's orbit) changes every 100,000 years, affecting the Earth's average temperature.
• Sunspots, occurring every 11 years, cause solar flares and may increase solar radiation to Earth by 0.2%.
• The carbon cycle involves plants storing carbon, animals consuming plants, and carbon being released back upon death.
• Volcanoes release ash and sulfur dioxide, causing short-term global cooling.
• Forest fires can cause short-term warming due to smoke release.

Evidence of past temperatures

• Sea Floor Sediments: the Chemical composition of aquatic organism fossils indicates ocean temperatures.
• Ice Cores: Trapped air bubbles reveal atmospheric composition and climate from the past; frequency of hydrogen and oxygen isotopes correlate to temperature.
• Lake Sediments: Pollen grains, spores, and diatoms in lake sediments record temperature data in layers called varves
• Tree Rings: Dendrochronology is used to measure environmental changes; growth ring width and shape indicate past climatic conditions and water availability.
• Fossils: Coral reef fossils indicate specific area's past temperature, water depth and sunlight conditions.

Debate on Climate Change

• Climate refers to changes in temperature and precipitation over 30 years.
• Projected CO2 increase may cause rising temperatures
• Greenhouse gases sustain a stable climate, but anthropogenic emissions are the main cause of climate change.
• High-pressure atmospheres cause the air density to increase, which in turn makes hotter temperatures.

Sustainability

• The 3 Es of sustainability are: Ecological integrity (environmental), Economic development, and Equity (social).
• Sustainability efforts must meet all 3 criteria to be truly sustainable

Millennium Development Goals (2000–2015)

• Eradicate poverty & hunger
• Promote gender equality
• Improve maternal health
• Ensure environmental sustainability
• Develop global partnerships for development
• Reduce child mortality
• Combat severe diseases
• Achieve universal primary education

Sustainable Development Agenda (2015–2030)

• Good health
• Clean water and sanitation
• Renewable energy
• Good jobs and economic growth
• Innovation and infrastructure
• Sustainable cities
• Responsible consumption
• Peace across every nation
• Active climate action

Atmospheric Processes

• Environmental Lapse Rate = 6.4°c - 6.5°c per 1000m
• Dry Adiabatic Lapse Rate = 9.8°c - 10°c per 1000m
• Saturated Adiabatic Lapse Rate = 5°c per 1000m on average, 4°c in humid air, 9°c in dry air
• Latent Heat of Condensation = 2260kJ for water

Plate Tectonics and Geological Features

• Continental Drift: Continents move due to seafloor spreading; the mid-Atlantic ridge contributes about an inch a year in the movement of the North American and Eurasian plates.
• Core: The inner core is a solid nickel-iron alloy, surrounded by the outer core of same material but liquid.
• Mantle: Semi-molten rock that flows, becoming more rigid with depth
• Crust: The outer layer of rock, Oceanic crust is thin and basaltic, while continental crust is thicker and granitic.
• Moho: The boundary between the lithosphere and the asthenosphere.
• Asthenosphere: The layer of the mantle from below the crust to the outer core.
• Lithosphere: The crust of the Earth and its outer structure
• Pangea: The proposed single ancient continent
• Palaeomagnetism: The study of Earth's past magnetic fields recorded in rocks.
• Divergent Plate Boundaries: Plates move apart
• Convergent Plate Boundaries: Plates move towards each other
• Constructive Plate Boundaries: Plates move apart, forming volcanoes
• Collision Plate Boundaries: Plates move together, forming mountain ranges
• Conservative Plate Boundaries: Plates slide past each other, causing earthquakes
• Destructive Plate Boundaries: Denser plate gets subducted
• Tectonic Plate: Large slabs of rock floating between the lithosphere and the asthenosphere
• Seafloor Spreading: Formation of oceanic crust that moves from mid-ocean ridges.
• Trench: Deep depressions where subduction occurs
• Fault: Fractures in rock along which movement occurs

Volcanic Activity

• Pillow lavas are typically basaltic and form underwater.
• Graben: A valley formed by a block of land moving downward.
• Island Arcs: Chains of volcanoes along convergent boundaries.

Earthquake Activity

• Seismic: Vibrations in the Earth's crust, caused by earthquakes
• Benioff Zones: Subduction zone where earthquakes occur due to plate friction.

Managing Volcanoes: Eyjafjallajökull 2010 Eruption

• Population of 300,000
• VEI of 4
• March 20, 2010 at 23:52
• No deaths
• 500 farmers evacuated and roads were shut down after warning signs of an eruption
• Local population evacuated because of the risks from ash
• Disrupted the fresh fish export industry.
• Flooding from a glacier on 14th April led to an evacuation of 700 people.

Managing Earthquakes: Kashmir 2005 Earthquake

• Population of 11.25 million
• Magnitude of 7.6
• October 8th, 2005 at 8:50 am
• On a destructive plate margin
• No local disaster planning
• Poor infrastructure
• Poor communications
• 100,000 deaths, mostly from collapsed buildings
• 3 million homeless
• Water and electricity lines were hit
• 87,350 died
• 138,000 injured
• 19km north-northeast of Muzaffarabad
• 500,000 people affected
• 250,000 farm animals died in collapsed barns
• 780,000 buildings destroyed
• 17,000 schools and major hospitals were destroyed

Sovereignty and Territorial Integrity

• State: An independent country with defined boundaries and a politically organised population under a single government.
• Nation: A group of people united by shared culture, history, language, or descent
• Sovereignty: Absolute authority states have over their territory and population.
• Territorial Integrity: States exercise sovereignty within internationally recognized boundaries.
• Norms: Customs and behaviors, that are in alignment with international law.
• Intervention: Actions of international organizations to resolve conflict or humanitarian crises.
• Geopolitics: The balance of global political power and international relations.

Challenges to Sovereignty

• Economic, political, social, and environmental factors, current political borders, transnational corporations (TNCs), and ethnic groups may cause issues

Challenges to Sovereignty in Ukraine

• Independence after Soviet Union collapse
• Geographical location issues in proximity to the EU and Russia
• Internal political disputes between pro-Russian and pro-Ukrainian speaking parts of the country
• Ethnic issues, 78% of the population of Ukraine, and 17% Russian
• Inability to build a common national identity

Challenges to Sovereignty in Ukraine

• Unrest in 2013 after failure to sign the EU Association Agreement.
• Invasion and annexation of Crimea in 2014.
• Conflict in the Donbass region with pro-Russian separatists supported by Russia.

Global Governance

• Global Peace Index: Used to determine the world's patterns of conflict
• Many multilateral treaties have been adopted by the United Nations to regulate conflict

Global Governance and Geopolitical Intervention

• International community provides aid and intervenes in conflict zones through UN missions, organizations, and NGOs. Theses require support from member states.
• Information and intelligence is exchanged through the sharing of data and ideas, with bilateral governmental aid.
• The military uses technology such as satellites, remote-controlled drones and weaponry for surveillance and airstrikes.

South Sudan

• Gained independence in 2011.
• Is landlocked in east-central Africa
• Population: 12 million.
• Oil exports account for 98% of the nation's income.
• The economy is underdeveloped with widespread poverty due to internal conflict.
• Subsistence agriculture is a key part of the economy
• Dinka and Nuer are the two largest ethnic groups.
• President and Vice-President caused political infighting in 2013, which turned into armed violence.
• Lack of sovereignty has caused the government to fail to protect its people.

International Intervention in South Sudan

• Necessary to resolve conflict and aid the population.
• Cooperation between the government of South Sudan, the UN, the Inter-Governmental Authority on Development for Eastern Africa, and other NGOs has been used to deliver intervention.
• The UN Peacekeeping Mission (UNMISS) has been used to consolidate peace and security in the region.
• UNICEF has been working to increase successful births where the fertility rate stands at 5.3.
• The World Health Organization is running an oral vaccination scheme for Cholera.
• The UN Office for the Co-ordination of Humanitarian Affairs helps provide safer drinking water and hygiene.