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Landmark United in Science report informs Climate Action Summit

Posted on 2 October 2019 by Guest Author

This is a re-post from the WMO

The world’s leading climate science organizations have joined forces to produce a landmark new report for the United Nations Climate Action Summit, underlining the glaring – and growing – gap between agreed targets to tackle global warming and the actual reality.

The report, United in Science, includes details on the state of the climate and presents trends in the emissions and atmospheric concentrations of the main greenhouse gases. It highlights the urgency of fundamental socio-economic transformation in key sectors such as land use and energy in order to avert dangerous global temperature increase with potentially irreversible impacts. It also examines tools to support both mitigation and adaptation.


“The Report provides a unified assessment of the state of our Earth system under the increasing influence of anthropogenic climate change, of humanity’s response thus far and of the far-reaching changes that science projects for our global climate in the future. The scientific data and findings presented in the report represent the very latest authoritative information on these topics,” said the Science Advisory Group to the UN Secretary-General’s Climate Action Summit.

“It highlights the urgent need for the development of concrete actions that halt the worst effects of climate change.”

The Science Advisory Group is co-chaired by WMO Secretary-General Petteri Taalas and Leena Srivastava, former Vice Chancellor of TERI School of Advanced Studies. It comprises highly recognized and respected natural and social scientists, with expertise in different aspects of climate change, including on mitigation and adaptation.

The report, which was coordinated by the World Meteorological Organization, aims to present a “transparent envelope” of authoritative and actionable cutting-edge science.  

The synthesis report consists of short summaries from contributing agencies: the World

Meteorological Organization (WMO), Global Atmosphere Watch, the United Nations Environment Programme (UNEP), Global Carbon Project, the Intergovernmental Panel on Climate Change (IPCC), Future Earth, Earth League and the Global Framework for Climate Services. The synthesis is complemented by longer, individual reports, presented as a package to a high-level science event on 22 September and then to world leaders at the Climate Action Summit on 23 September.


Highlights from the report include:

The Global Climate in 2015-2019

World Meteorological Organization (WMO)


Warmest five-year period on record

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°Celsius (± 0.1°C) above pre-industrial (1850–1900) times. Widespread and long-lasting heatwaves, record-breaking fires and other devastating events such as tropical cyclones, floods and drought have had major impacts on socio-economic development and the environment.


Continued decrease of sea ice and ice mass

Arctic summer sea-ice extent has declined at a rate of approximately 12% per decade during 1979-2018. The four lowest values for winter sea-ice extent occurred between 2015 and 2019.

Overall, the amount of ice lost annually from the Antarctic ice sheet increased at least six-fold between 1979 and 2017.  Glacier mass loss for 2015-2019 is the highest for any five-year period on record.


Sea-level rise is accelerating, sea water is becoming more acidic

The observed rate of global mean sea-level rise accelerated from 3.04 millimeters per year (mm/yr) during the period 1997–2006 to approximately 4mm/yr during the period 2007–2016. This is due to the increased rate of ocean warming and melting of the Greenland and West Antarctica ice sheets. There has been an overall increase of 26% in ocean acidity since the beginning of the industrial era.


Record Greenhouse Gas Concentrations in the Atmosphere

WMO Global Atmosphere Watch

Levels of the main long-lived greenhouse gases, carbon dioxide (CO2), methane (CH4)) and nitrous oxide (N2O) have reached new highs.

The last time Earth’s atmosphere contained 400 parts per million COwas about 3-5 million years ago, when global mean surface temperatures were 2-3°C warmer than today, ice sheets in Greenland and West Antarctica melted, parts of East Antarctica ice had retreated, all causing global see level rise of 10-20m compared with today.

In 2018, global COconcentration was 407.8 parts per million (ppm), 2.2 ppm higher than 2017. Preliminary data from a subset of greenhouse gas monitoring sites for 2019 indicate that COconcentrations are on track to reach or even exceed 410 parts per million (ppm) by the end of 2019.

In 2017, globally averaged atmospheric concentrations of CO2 were 405.6 ±0.1 ppm, CH4at 1859 ±2 parts per billion (ppb) and N2O at 329.9 ±0.1 ppb. These values constitute, respectively, 146%, 257% and 122% of pre-industrial levels (pre-1750).

The growth rate of CO2 averaged over three consecutive decades (1985–1995, 1995–2005 and 2005–2015) increased from 1.42 ppm/yr to 1.86 ppm/yr and to 2.06 ppm/yr


Global Carbon Budget

Global Carbon Project

Carbon dioxide emissions grew 2% and reached a record high of 37 billion tonnes of CO2 in 2018. There is still no sign of a peak in global emissions, even though they are growing slower than the global economy.

Current economic and energy trends suggest that emissions will be at least as high in 2019 as in 2018. Global GDP is expected to grow at 3.2% in 2019, and if the global economy decarbonized at the same rate as in the last 10 years, that would still lead to an increase in global emissions.

Despite extraordinary growth in renewable fuels over the past decade, the global energy system is still dominated by fossil fuel sources. The annual increase in global energy use is greater than the increase in renewable energy, meaning the fossil fuel use continues to grow. This growth needs to halt immediately.

The net-zero emissions needed to stabilize the climate requires both an acceleration in use of non-carbon energy sources and a rapid decline in the global share of fossil fuels in the energy mix. This dual requirement illustrates the scale of the challenge.

Natural COsinks, such as vegetation and oceans, which remove about half of all emissions from human activities, will become less efficient at doing so. This underscores the need to reduce deforestation and expand natural COsinks, particularly those in forests and soils that can be improved by better management and habitat restoration.


The emissions gap – where we are and where we need to be

United Nations Environment Programme (UNEP)

The UNEP Emissions Gap Reports, with the tenth edition being published this November, assess the latest scientific studies on current and estimated future greenhouse gas emissions; they compare these with the emission levels permissible for the world to progress on a least-cost pathway to achieve the goals of the Paris Agreement. This difference between “where we are likely to be and where we need to be” is known as the emissions gap.

Global emissions are not estimated to peak by 2030, let alone by 2020, if current climate policies and ambition levels of the Nationally Determined Contributions (NDCs) are maintained. Preliminary findings from the Emissions Gap Report 2019 indicate that greenhouse gas emissions continued to rise in 2018.

The emissions gap in 2030 between emission levels under full implementation of conditional Nationally Determined Contributions (NDCs) and levels consistent with least-cost pathways to the 2°C target is 13 GtCO2e. If just the unconditional NDCs are implemented, the gap increases to 15 GtCO2e. The gap in the case of the 1.5°C target and 2°C target is 29 GtCO2e and 32 GtCO2e respectively.

Current NDCs are estimated to lower global emissions in 2030 by up to 6 GtCO2e compared to a continuation of current policies. This level of ambition needs to be roughly tripled to align with the 2°C limit and must be increased around fivefold to align with the 1.5°C limit.

Implementing unconditional NDCs, and assuming that climate action continues consistently throughout the twenty-first century, would lead to a global mean temperature rise between 2.9°C and 3.4°C by 2100 relative to pre-industrial levels.

If NDC ambitions are not increased immediately and backed up by action, exceeding the 1.5°C goal can no longer be avoided. If the emissions gap is not closed by 2030, it is very plausible that the goal of a well-below 2°C temperature increase is also out of reach.

A substantial part of the technical potential can be realized through scaling up and replicating existing, well-proven policies – such as switching to renewable energy and reforestation -  that simultaneously contribute to key sustainable development goals.


Intergovernmental Panel on Climate Change (IPCC)

Three IPCC Special Reports released in 2018 and 2019 assess complementary and specific aspects of climate change, ahead of the Sixth Assessment Report.

The Special Report on Global Warming of 1.5°C states that limiting warming to 1.5ºC is not physically impossible but would require unprecedented transitions in all aspects of society. There are clear benefits to keeping warming to 1.5 ºC compared to 2 ºC or higher. Every bit of warming matters.

Limiting warming to 1.5ºC can go hand in hand with reaching other world goals such as achieving sustainable development and eradicating poverty.

The Special Report on Climate Change and Land stressed that land is already under growing human pressure and climate change is adding to these pressures. At the same time, keeping global warming to well below 2ºC can be achieved only by reducing greenhouse gas emissions from all sectors including land and food.

"The report shows that better land management can contribute to tackling climate change, but land is not the only solution. Reducing greenhouse gas emissions from all sectors including energy is essential if global warming is to be kept as close as possible to 1.5ºC above pre-industrial levels."

On 25 September 2019, the IPCC is due to release the Special Report on the Ocean and Cryosphere in a Changing Climate.


Climate Insights

Future Earth and Earth League

Consolidated evidence reinforces human influence as the dominant cause of changes to the Earth system, in a new geological epoch, the Anthropocene.

Growing climate impacts increase the risks of crossing critical tipping points. These refer to thresholds that, if crossed, lead to far-reaching, in some cases abrupt and/or irreversible changes.

There is a growing recognition that climate impacts are hitting harder and sooner than climate assessments indicated even a decade ago.

As climate change intensifies, cities are particularly vulnerable to impacts such as heat stress and can play a key role in reducing emissions locally and globally.

Strategies for mitigation and for upscaling adaptive risk management are necessary going forward. Neither is adequate in isolation given the pace of climate change and magnitude of its impacts. 

Only immediate and all-inclusive action encompassing: deep de-carbonization complemented by ambitious policy measures, protection and enhancement of carbon sinks and biodiversity, and efforts to remove CO2 from the atmosphere, will enable us to meet the Paris Agreement.


Global Framework for Climate Services

Climate and early warning information services should underpin decision-making on climate action for adaptation.

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Comments 1 to 4:

  1. Urgent world-scale action has long been needed to address climate change, and the most effective tool to use is the profit motive.  Here's the vision: 1st World green citizens in their millions persuade their contact companies to partner with 3rd World co-ops and companies starting with the Philippines as modeling country to set up high-profit green industries.  Projects: Ethanol distilleries fed by sweet sorghum farms.  Thousand-hectare agroforests with processing factories for export production.  Geothermal plants.  Mini-dam hydropower nets.  Methane digesters and E85 engines for on-site power generation.  E85 & electric transports.  Low-cost solar cells.  Forest resorts. All-electric metals industries.  Agroforest water supply, toll roads, etc.  Current billion-dollar Green Funds should finance the projects at 75% levels due to sure repayment plus interest income incident to the projects' high profitability.  Spread out tropics wide, the projects should sequester atmospheric CO2 at billion-ton levels each year for all time, while employing millions of poor and creating huge markets for all involved companies.   Details:

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  2. Fermin Francisco @1

    The profit motive is indeed a useful tool. We see this because wind power is now so economically attractive it makes a profit - assuming you are replacing old worn out coal fired plant for example.

    However there is no real profit in replacing more recently built coal fired plant with renewables, and planting forests, carbon capture and storage etc, unless the government subsidises these things, or alternatively a carbon tax penalises continued use of fossil fuels. Remember those forests need to remain unused for decades, they cannot be sold for profit as such.

    So the climate problem is a political problem, where your lobbying efforts are probably better directed mainly at governments.

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  3. This comprehensive and robust report improves awareness and understanding. And improving awareness and understanding should reduce anxiety and fear.

    But the way people have been winning competitions for status based on perceptions of popularity and profitability has unsustainably developed incorrect and harmful beliefs and actions. The result is that this increased awareness and understanding actually increases anxiety and fear.

    This long comment is presented to establish context for a critical response to suggestions that the pursuit of profit can and will be “The solution” to the climate impact problem.

    For a long time, like many others, I have pursued increased awareness and understanding of what is required for humanity to develop a sustainable and sustainably improving future. I have learned that sustainable development requires anxiety and fear to be reduced. And improved awareness and understanding is the only way to sustainably reduce anxiety and fear.

    However, because of the incorrect direction of development, particularly during the past 30 years, this report increases anxiety and fear. It increases justified anxiety and fear by showing how much worse the current situation is than it needed to be, with the related understanding that the required corrections are still being successfully harmfully resisted (justified fear expressed by the likes of Greta Thunberg).

    A more important understanding is that the improving awareness and understanding increases anxiety and fear in people who have developed beliefs that are not supported by the improving awareness and understanding, particularly if those unsustainable beliefs are used to defend developed interests to personally benefit from unsustainable and harmful activities. That increased fear is regarding how much the required correction will cost people who have overdeveloped their beliefs and actions in an incorrect and unsustainable direction.

    That understanding leads to an awareness and understanding that many, but not all, influential “winners and wanna-be-winners” unethically make-up and promote misleading stories. They do it to get as many people as possible to continue to be supporters of resisting the corrections of understanding that are required for humanity to develop a sustainable and sustainably improving future. They do it out of fear of personal loss.

    That fearful resistance has developed in a variety of socioeconomic-political systems and related to many matters, not just climate impacts. But it has powerfully developed in democratic consumerism based systems, most notably in systems that have not developed effective governance ruled by the pursuit of “Development of Sustainable Improvements, Helpfulness to Others”.

    Marketing science has improved the understanding of how people think and behave in response to marketing. Regrettably, driven by pursuits of winning in politics and consumerism, it has developed the understanding that misleading people into being anxious and fearful can be beneficial when it is done 'to help people resist the corrections that would be required by improved awareness and understanding'.

    It is obvious that through the past 30 years "the profit motive" has failed to be helpful to the future of humanity, particularly because of the freedom to develop and deliver misleading marketing without a significant personal consequence. Through the past 30 years many of those among the population who are wealthier - the people that the likes of Adam Smith and John Stuart Mill believed would end up governing helpfully because of their higher level of awareness and understanding - have acted harmfully contrary to improving awareness and understanding and its application to develop sustainable improvements for humanity.

    The "pursuit of profit" is not the problem. The lack of Caring Helpful governance in pursuit of, and improvement of, the Sustainable Development Goals is the problem. The problem is the way that pursuit of popularity and profit can over-power the governance of any system, especially a system that encourages more freedom for people to "believe and do as they please".

    SkS, and many other initiatives, have been developed to try to help improve awareness and understanding. SkS is focused on the Climate Action goal. But all of the SDGs face similar unwarranted resistance to being achieved and improved on.

    Only time will tell how bad things will become before anxiety and fear is sustainably reduced to the point where undeserving promoters of unjustified anxiety and fear will fail to significantly influence what is going on.

    Hopefully the future of humanity will not suffer too much harm from the 'pursuits of popularity and profit' before current day leadership dedicates its efforts to improving awareness and understanding in pursuit of sustainable improvements for the benefit of the future of humanity (learning from people who are dedicated pursuers of improved awareness and understanding and leading on that basis rather than unethically prolonging unsustainable popularity or profitability).

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  4. From The Financial Times: "The limits of the pursuit of profit"

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