Thread by @Peters_Glen

THREAD

The world's leading climate science organisations joined forces to outline the latest climate trends for the #UNClimateSummit.

What does the report say?

public.wmo.int/en/media/press…
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2. The average global temperature for 2015–2019 is on track to be the warmest of any equivalent period on record.

It is currently estimated to be 1.1°C (±0.1°C) above pre-industrial (1850–1900) times & 0.20±0.08°C warmer than the global average temperature for 2011–2015.

3. The observed rate of global mean sea-level rise increased from 3.04 mm/yr during the period 1997–2006 to approximately 4 mm/yr during the period 2007–2016.

The accelerated rate is due to increased ocean warming & land ice melt from Greenland & West Antarctica.

4. The ocean absorbs nearly 25% of CO₂ emissions, alleviate the impacts of climate change.

But, observations show an increase in ocean acidity of 26% since the industrial era, which is detrimental to marine life & ocean services.

5. Fossil CO₂ emissions, 90% of total CO₂ emissions, continue to grow by over 1% annually & grew by 2% in 2018, reaching a record high of 37 billion tonnes of CO₂.

6. Emissions from the combustion of coal may have peaked in 2013, but growth of coal emissions resumed in 2017. Emissions from oil and gas continue to grow rapidly.

7. The global energy system is still dominated by coal, oil, & gas. Biomass & hydro continue to grow strongly. Nuclear is loosing its share in the energy system. Wind & solar are growing rapidly, but still too slow to cover the annual increase in energy use.

8. Despite the global upward trend, emissions from the USA & the EU have declined over the past decade, growth
in China’s emissions has slowed significantly since the 2000s, Indian emissions continue to grow strongly.

More needs to be done by all countries to reduce emissions.

9. Per capita emissions vary widely between countries. USA is one of the highest in the world, China & the EU have equal per capita emissions, somewhat higher than the global average. India has the lowest per capita emissions of the big emitters.

10. Natural CO₂ sinks, such as vegetation & oceans, remove about half of all emissions from human activities.

This important benefit underscores the need to reduce
deforestation & expand natural CO₂ sinks.

11. There are many options moving forward. Rapid-short term reductions are required to meet the goals of the Paris Agreement.

12. Levels of CO₂, CH₄, & N₂O have reached new highs.

A full analysis for 2017 for the three main GHG shows that globally averaged atmospheric concentrations of CO₂
were 406ppm, CH₄ 1859ppb, & N₂O 330ppb, 146%, 257% & 122% of above pre-industrial levels (pre-1750).

13. The Annual Greenhouse Gas Index from 1990 to 2018 showing radiative forcing by long-lived greenhouse gases (GHGs) increased by 43%, with CO₂ accounting for about 80% of this increase...

14. The emissions gap between current emission pledges (NDCs) in 2030 & pathways consistent with 2°C is 13-15GtCO₂-eq, & for 1.5°C is 29-32GtCO₂-eq.

The emission pledges would lead to a global mean temperature rise between 2.9°C and 3.4°C by 2100.

15. The higher the temperature increase, the greater the risk of impacts. The more emissions reduced, the lower the risks (but risks will never reach zero).

16 (bonus). No matter how much mitigation happens in the short-term, it is likely that 1.5°C will be breached ~2030, 2°C can be avoided with rapid short-term action.

The world needs to prepare for climate impacts, even in a Paris-compliant world.

economist.com/briefing/2019/…

17/17. The report contains much more information, so download a copy! I only skimmed on the areas where I am most active or interested.

There are also more detailed reports on each of the sections.

public.wmo.int/en/media/press…