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Explore the current state of climate change, its impacts, and the urgent need for action. Learn about the risks, rising sea levels, extreme weather events, and their implications for human health and the planet. Discover the importance of limiting global warming to avoid dangerous consequences. Find out what can be done to mitigate and adapt to climate change.
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Climatechange:Where do we stand?Why should we care? Prof. Lučka Kajfež Bogataj Universityof Ljubljana, Slovenia
One person energy need ≈ 1GigaJ per day LIFESTYLE TODAY IS HIGLY ENERGY CONSUMING
Primary energy consumption and total global emissions are increasing
Fate of anthropogenic CO2 emissions (2008–2017) Sources = Sinks 17.3 GtCO2/yr 44% 34.4 GtCO2/yr 87% 29% 11.6 GtCO2/yr 13% 5.3 GtCO2/yr 22% 8.9 GtCO2/yr 5% 1.9 GtCO2/yr Budget Imbalance: (the difference between estimated sources & sinks)
In a number of regions, impacts are already underwayUENCE: Some changes in extreme weather and climate events observed since ~1950 are linked to human activity • decrease in cold temperature extremes • increase in warm temperature extremes • increase in extreme high sea levels • increase in the number of heavy precipitation events
CO2 (ppm) 405 2019 +46% 1850 280 180 800.000 years
Regional aspects of surface warming 2°C 4°C 1.5°C °C Knutti et al, Nat. Geo., 2015
Regional aspects of precipitation change 2°C 4°C 1.5°C % precipitation change • Water cycle change : • for 50% of world’s population at +2°C • for 40% of land surface at +3°C Sedlacek and Knutti, 2014; Knutti et al, Nat. Geo., 2015
ProjectionsEurope (RCP4.5)2081-2100 versus 1986-2005 Temperature (oC) Precipitation (%) winter summer winter half summer half
The Mediterranean is regarded as a climate change hot spot 2 main reasons • stronger warming of the regional land-based hot extremes compared to the mean global temperature warming • substantial decreases in mean precipitation with associated substantial increases in dry spells.
Paris agreement takes effect in 2020 But the world IS NOT on track • Intended Nationally Determined Contributions (INDCs) would lead to will lead to a warming of 2.8°C, current government policies still lead to a warming of 3.6°C • INDCsare totaly incompatible with 2°C objective • 1.5°C temperature increase could be reached even before 2025
1.5°C in the Paris Agreement • Paris Agreement included the aim to hold the increase in the global temperature to well below 2 °C and to pursue efforts to limit the temperature increase to 1.5 °C above pre-industrial levels. • New science outlines how the risks and impacts of climate change increase between 1.5°C and 2°C .
How Close Are We to 1.5°C? If the current warming rate continues, the world would reach human-induced global warming of 1.5°C around 2040
The view to 2050 and beyond Source: UNEP
How we can limit global warming to 1.5°CThe most important things to do in the next 5 to 10 years
How to invest in mitigation IEA, 2015
Energy efficiency: tackling energy loss is essentialInnovative solutions must fundamentally change the way we produce, store, transport and use energy
For limiting global warming to below... 1,5°C • global net anthropogenic CO2 emissions must decline by about 45%(40-60%) from 2010 levels by 2030, • reaching net zero by 2050 (2045–2055) 2°C • CO2emissions should decline by about 20%(10-30%) by 2030 and • reach net zero around 2075 (2065–2080)
All pathways that limit global warming to 1.5°C... • project the use of carbon dioxide removalon the order of 100–1000 GtCO2 over the 21st century. • require rapid and far-reaching transitions in energy, land, urban and infrastructure and industrial systems. • These systems transitions are unprecedented in terms of scale and imply deep emissions reductions in all sectors, a wide portfolio of mitigation options and a significant upscaling of investments in those options
Ifwe are serious about “saving the planet”, then this requiresa fundamental rethinking in economy model • Reduction of resource consumption • Management that emphasize optimization, not maximization • Behavioural changes
Where do we stand? 1. Earth has entered a new geological epoch – the Anthropocene – with profound implications for humanity and the relative stability of the Earth system. 2. Earth is approaching tipping points due to human pressures. 3. Risks of extreme weather are increasing. 4. Rising sea levels and ocean acidification are growing threats.
Why should we care? 5. The costs of climate change are already being felt today and will increase in the future. 6. Human health is at risk from air pollutants that alter the climate, and the impacts of a changing climate, which are decreasing food security and increasing the risks of disease and heat stress. 7. Climate change is likely to exacerbate the risk of large-scale migration and civil unrest. .
How can we avoid dangerous impacts? 8. The world needs to act faster: deeper cuts are needed to reduce risk of global average temperature rising 2 °C above pre-industrial levels. A pathway of halving global emissions every decade is consistent with this goal. 9. It is possible for the world to meet Paris Agreement targets if nation states cooperate and coordinate mitigation efforts. Carbon pricing is an important policy tool that would create substantial revenues amounting to potentially several percent of GDP. 10. Adaptation and resilience building are necessary even if the world succeeds with aggressive international action to reduce emissions of greenhouse gases.