Past temperatures

Karsten Haustein’s climate modelling presentation

Key Facts – The Science

Earth is getting hotter and 97% of scientists agree that it’s caused by human activity.*
Global warming is causing our climate to change and it’s happening now. Effects include more frequent and severe extreme weather events such as droughts, dry spells, flooding and hurricanes as well as rising sea levels.
In 1950, annual globalemissions were around 6 gigatonnes. Now they are around 37 gigatonnes
There already exists a 1 in 20 chance that the 2.2 trillion tons of carbon dioxide in the Earth’s atmosphere could cause an existential warming threat. Basically, for a safe climate we must: 
1. Zero out CO2 emissions by 2050 (which means acting now) 
2. Rapidly limit super pollutants like HFCs and methane
3. Undertake atmospheric carbon removal.

Key Facts – The Politics

IPCC states ‘in order to limit warming to 1.5°C emissions need to reach maximum by 2030 and achieve net zero CO2 emissions globally by 2050 and concurrent deep reductions in emissions of non-CO2 forcers, particularly methane’
Current UK target is 80% reduction in CO2 emissions from 1990 levels by 2050.
Therefore there is a gap between what is required to limit the catastrophic effects (listed above) and what the UK is currently committed to.
Fossil fuels as a share of final energy consumption remains stubbornly around 80%—roughly the same percentage as at the beginning of the 1990s. And this status quo is supported by fossil fuel subsidies and tax breaks, amounting to an estimated US$373 billion in 2015 according to the OECD and IEA. OECD, 2018. 
Current warming is at about 1 °C above pre-industrial levels, with 17 of the 18 warmest years in the 136-year record having occurred since 2001.
If we continue to emit CO2 at current rates for the next two decades, it is unlikely that we will be able to limit the increase in average global surface temperature to 3°C (compared with the late 19th century, the usual benchmark), let alone to ‘well below 2°C’, the target of the Paris Agreement.
Research implies that, even if the Paris Accord target of a 1.5 °C to 2.0 °C rise in temperature is met, we cannot exclude the risk that a cascade of feedbacks could push the Earth System irreversibly onto a “Hothouse Earth” pathway.
A rise of 3°C would be extremely dangerous, taking us to a temperature we have not seen on this planet for around 3 million years .
Globally, disasters triggered by weather-related hazards caused as much as US$320 billion in losses in 2017, significantly higher than average, as well as thousands of deaths. https://
Extreme weather events represent the greatest risk to the future development of humanity, according to the World Economic Forum’s 2018 Global Risk Report.
With each fraction of a degree warming, we are further at risk of uncontrollable positive feedback loops leading to runaway climate change and ‘global hothouse’ effect. (infographic here:
The oceans alkalinity has decreased by 30% since 1800 and is projected to decrease by 150% by 2100. The sixth Extinctionby Elizabeth Kolbert
The oceans pH level were at 8.2 at the start of the Industrial Revolution, and are at 8.1 now. It is projected that the pH level will further decrease to 7.8 by the end of this century. This pH has not been experienced for more than 20 million years (NOAA, 2013)
More than 26,000 species are threatened with extinction; that is 41% of all amphibians, 34% of all conifers, 33% of reef-building corals, 31% of sharks and rays, 25% of all mammals, and 13% of all birds.
The total number of vertebrate species that went extinct in the last century would have taken about 800 to 10,000 years to disappear if the background rate had prevailed. Modern extinction rates are exceptionally high, and they are increasing. That suggests a mass extinction under way—the sixth of its kind in Earth’s 4.5 billion years of history. On human time scales, this loss would be effectively permanent because in the aftermath of past mass extinctions, the living world took hundreds of thousands to millions of years to rediversify.
The combined effects of ambient (outdoor) and household air pollution cause about 7.0 million premature deaths every year.

Potential of hydro power

Recent studies estimate there is a remaining viable hydro potential of 850 to 1550 megawatts in the UK. This represents approximately 1 to 2% of current UK generating capacity

The potential for further practical and viable hydroelectricity power stations in the UK is estimated to be in the region of 146 to 248 MW for England and Wales.

Recent resource studies have indicated that there is a practical potential for a further 2GW of capacity in the UK. [this is mostly in Scotland]

Life-cycle emissions of renewables, vs fossil power with CCS

“For a climate protection scenario, we project life-cycle emissions from fossil fuel carbon capture and sequestration plants of 78–110 gCO2eq kWh−1, compared with 3.5–12 gCO2eq kWh−1 for nuclear, wind and solar power for 2050. Life-cycle emissions from hydropower and bioenergy are substantial (∼100 gCO2eq kWh−1), but highly uncertain. We find that cumulative emissions attributable to upscaling low-carbon power other than hydropower are small compared with direct sectoral fossil fuel emissions and the total carbon budget. Fully considering life-cycle greenhouse gas emissions has only modest effects on the scale and structure of power production in cost-optimal mitigation scenarios.”

Lifecycle emissions of batteries

Working out ecological footprints is complex, but a large component is the energy used in manufacture: using clean energy to manufacture, and paying attention to supply sources can significantly minimise the ecological footprint of battery production

Potential to minimise ecological footprints of different battery technologies