V2 Flashcards
Current state and observed changes in climate:
Regionale Unterschiede in der Erwärmung:
Observed precipitation changes:
Observed changes:
Observed changes in extremes:
Current state of climate:
- the last five years were the five warmest on record globally and on average over 1.1°C warmer than during pre-industrial times
- 2019 was the second warmest year
- 2010-2019 was the warmest decade
- globally already many extensive impacts of climate change in physical, chemical and biological systems are detectable and verifyable
Natural and anthropogenic drivers in the climate system:
- External drivers
- plate tectonics
- orbital parameters
- solar activity
- volcanism
- Internal climate variability
- Anthropogenic drivers
- greenhouse gas emissions
- land use change
Germany under Climate Change:
Natural greenhouse effect:
- radiation equilibrium temperature without atmosphere: -18°C
- real average temperature: +15°C
- anthropogenic effect on top
Drivers:
Development of important GHG:
Natural and anthropogenic forcing:
It‘s getting hot in here…!
does the future look like?
Example 1: Ice-albedo-feedback
Heat wave 2019:
-
Temperature records:
- Germany 42,6°C (2 K above old one)
- almost everywhere in Europe
Excursus: probability density of extremes
Example 3:
Correlation between temperature and CO2
Example 2: Biogeochemical feedback mechanisms
Feedbacks and timescales:
Tipping points, 1.5°C is the right target!
Risks and impacts:
Important global tipping points in the climate system:
Further severe, long-term consequences:
- Loss of biodiversity and mass extinction of species
- Strong increase of extremes
- Sea level rise
- Mass migration
- High adaptation and mitigation costs
- many other ecological, social and economic consequences in all areas of society
How much time do we have left for the 1.5°C target?
GHG: sources and sinks
How much time do we have left?
How much time do we have left?
Reduction paths from 2020 for 1,5°C target:
- If we start in 2022, time for transition shorter by 4 years
Reduction pathways 2020 for the 1.5°C target:
Reduction pathways 2020 for the 1.5°C target:
Where are we currently?
Conclusions:
- The global increase in temperature since the industrialization has passed 1.1°C
- To avoid global tipping points and severe consequences in the earth system, 1.5°C increase in temperature should not be surpassed (⇒ Paris Climate Agreement)
- To achive this, it takes the quickest possible transformation towards a carbonneutral society globally
- Current climate targets all around the world are far from sufficient
- Every year delay will cost a large amount of time and money
Cost-benefit of climate mitigation:
Example: alternatives to fossil fuels
potential of renewable energies
