What climate tipping points should we be looking out for?

Posted by colin.hargreaves@aoc.org.au on July 24, 2014 at 2:20 AM Comments comments (0)

by Andrew Glikson, in https://theconversation.com/what-climate-tipping-points-should-we-be-looking-out-for-27108" target="_blank">The Conversation, 14 July 2014


The concept of a “tipping point” – a threshold beyond which a system shifts to a new state – is becoming a familiar one in discussions of the climate.


Examples of tipping points are everywhere: a glass falling off a table upon tilting; a bacterial population hitting a level where it pushes your body into fever; the boiling point of water, or a cube of ice being thrown into warm water, where it rapidly melts.


The ice cube is a poignant example, because scientists now fear that West Antarctica’s ice sheets are also heading towards irreversible melting.


Likewise, the recent discovery of deep canyons beneath the Greenland ice sheet raises concerns regarding its stability.


The history of the atmosphere, oceans and ice caps indicates that, once changes in the energy level which drive either warming or cooling reach a critical threshold, irreversible tipping points ensue.


An example is a process called “albedo flip”, where a small amount of melting creates a film of water on top of the ice. The water absorbs infrared radiation and melts more ice, leading to runaway melting of ice sheet. The opposite process occurs where the freezing of water results in reflection of radiation to space, leading to cooling and freezing of more water.


Other examples are abrupt warming episodes during glacial states, termed “interstadials”, for example the “Dansgaard-Oeschger” warming cycles which occurred during the last glacial period between about 100,000 and 20,000 thousand years ago, which caused large parts of the North Atlantic Ocean to undergo temperature changes of several degrees Celsius within short periods. Other examples are points at which a glacial state ends abruptly to be replaced by rapid glacial termination.


Over the threshold


An increase in global temperatures can lead to a threshold representing the culmination and synergy of multiple processes, such as release of methane from permafrost or polar ocean sediments, retreating sea ice and ice sheets, warming oceans, collapse of ocean current systems such as the North Atlantic Thermohaline Current and – not least – large scale fires.


A major consequence of warming of ice sheets is the increase in supply of cold fresh melt water to adjacent oceans, such as the abrupt cooling of the North Atlantic Ocean inducing rapid freezing events (stadials), as represented by the “Younger dryas” event (12,900-11,700 years ago), or the rapid melting of Laurentian ice cap about 8500 years ago and related abrupt cooling events in Europe and North America.



Satellite images of Greenland, July 8 and July 12, 2012. White shows remaining ice; red shows melt; pink shows probable melt; grey shows ice-free; dark grey means no data. NASA

Click to enlarge

The question is whether the post-18th century global warming trend may culminate in a major tipping point or, alternatively, is represented by an increase in disparate extreme weather events, as are currently occurring around the world.


A potential indicator of such tipping point may be represented by a collapse of the North Atlantic Thermal Circulation, which would lead to a sharp, albeit transient, temperature drop in the North Atlantic Ocean, North America and Western Europe. Evidence for a weakening of the North Atlantic deep water circulation by about 30% between 1957 and 2004 has been reported in Nature as well as by other researchers.


The question of tipping points is of critical importance since it affects future climate projections and adaptation plans. In this regard the latest Intergovernmental Panel on Climate Change report leaves the question of tipping points open.


The crucial question


So how likely is the current climate change trend to reach a tipping point, and if so of what magnitude and on what time scale?


General circulation climate models which attempt to delineate overall future climate trends are limited in their capacity to predict the precise timing, location and magnitude of abrupt climate and weather events with confidence.


Since the 19th century the rise in the energy level of the atmosphere has reached a level of more than 3 degrees Celsius when the masking effects of sulphur aerosols are discounted. This degree of temperature rise is just under the energy rise level associated with the last glacial termination between about 16,000 and 10,000 years ago.


The atmosphere-ocean system continued to warm following the peak El-Nino event of 1998. Most of the warming occurred in the oceans, whose mean temperature has risen by about 0.3C since 1950.


The current rise in atmospheric CO2 of about 2 parts per million CO2/year, reaching 401.85 parts per million at the Mauna Loa Observatory in Hawaii in May 2014, exceeds rates observed in the geological record of the last 65 million years.


An atmospheric CO2 level of 400 parts per million is estimated for the Miocene, about 16 million years ago, when mean temperatures have reached 3 to 4 degrees Celsius above those of pre-industrial temperatures. Economically available fossil fuel reserves, if used, are capable of returning the atmosphere to tropical state such as existed during the early to mid-Eocene prior to the formation of the Antarctic ice sheet about 32 million years ago.


The evidence indicates that, since the mid-1980s, the Earth is shifting from a climate state that favoured land cultivation since about 7000 years ago to a climate state characterised by mean global temperatures about 2-3 degrees Celsius above pre-industrial levels.


At this level, extreme weather events would render large parts of the continents unsuitable for agriculture. The accelerated melting of the Greenland and west Antarctic ice sheets could lead to conditions akin to those of the Pliocene, before 2.6 million years ago, when sea level were between 5 and 40 metres higher than at present, as estimated by the US Geological Survey.


The evidence indicates the climate may be tracking toward – or is already crossing – tipping points whose precise nature and timing remain undefined, depending on the extent to which ice sheet melting is retarded due to hysteresis. The increase in frequency and intensity of extreme weather events around the globe may represent a shift in state of the atmosphere-ocean system. There is no alternative to a global effort at deep cuts of carbon emissions coupled with fast-tracked CO2 sequestration.


As Professor Joachim Schellnhuber, Germany’s climate advisor and Director of the Potsdam Climate Impacts Institute, has said:


We’re simply talking about the very life support system of this planet.

8 charts that show how climate change is making the world more dangerous

Posted by colin.hargreaves@aoc.org.au on July 15, 2014 at 1:45 AM Comments comments (0)

Disasters including storms, floods and heatwaves have increased fivefold since the 1970s, UN finds

By Suzanne Goldenberg

Forget the future. The world already is nearly five times as dangerous and disaster prone as it was in the 1970s, because of the increasing risks brought by climate change, according to a new report from the World Meteorological Organisation.


The first decade of the 21st century saw 3,496 natural disasters from floods, storms, droughts and heat waves. That was nearly five times as many disasters as the 743 catastrophes reported during the 1970s – and all of those weather events are influenced by climate change.

Photo Alex Brandon/AP

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No False Choices: To Preserve A Livable Climate, We Need To Slash Both CO2 And Methane

Posted by colin.hargreaves@aoc.org.au on July 12, 2014 at 2:15 AM Comments comments (0)

by Joseph Romm


Natural gas can either leak out as methane, or be flared as CO2 before going to market. CREDIT: Shutterstock

he bad news is that humanity has dawdled for so long that our only realistic chance to avoid multiple, irreversible, catastrophic climate impacts is to slash both carbon dioxide and the “super pollutants” like methane sharply starting as soon as possible.


As Dr. Jeffrey Sachs, Director of Columbia’s Earth Institute, told MSNBC Tuesday:


We’ve been told the basic falsehood that somehow fracking is going to save us, which is basically the opposite of the truth.


What kind of good news can the world expect after ignoring near-unanimous expert advice for 25 years? Well, we can almost certainly avert the worst impacts for billions of people, but only by aggressively curtailing both CO2 (which lingers in the atmosphere for hundreds of years) and the super pollutants (which are much more potent at trapping heat in the short-term than CO2, but which have a much shorter atmospheric lifetime).


Some confusion has been generated on this issue by a Tuesday New York Times piece, “Picking Lesser of Two Climate Evils,” which frames our optimum climate strategy as a choice between targeting CO2 and targeting super pollutants like methane, hydrofluorocarbons, and black carbon, that together cause some 40% of the warming we’re experiencing now.


But that is a “false choice,” as longtime NASA climate scientist Drew Shindell explained to me. We have to do both to maximize lives saved and minimize the chances of dangerous warming. That’s a point Climate Progress has made consistently.


The New York Times piece builds off an analysis by climatologist Raymond Pierrehumbert on “Short-Lived Climate Pollution” (SLCP). He concludes that an “implementation of SLCP mitigation that substitutes to any significant extent for carbon dioxide mitigation will lead to a climate irreversibly warmer than will a strategy with delayed SLCP mitigation. SLCP mitigation does not buy time for implementation of stringent controls on CO2 emissions.”


I think that conclusion is correct: Absent an effort to sharply reduce CO2 emissions ASAP, everything else is a sideshow if not an outright distraction.


But I think this assertion by Pierrehumbert is not tenable: “There is little to be gained by implementing SLCP mitigation before stringent carbon dioxide controls are in place and have caused annual emissions to approach zero.” That seems to me a false choice, suggesting that humanity is somehow incapable of reducing all greenhouse gases at the same time.


Also, it ignores the risk that we might cross irreversible warming thresholds in the coming decades that further accelerate warming — such as permafrost melt — before the impact of the CO2 reductions can be felt. And it ignores the very low cost of reducing SLCPs compared to the relatively higher cost of reducing CO2 as you approach zero (i.e. after you have exhausted all of the low-cost CO2-reduction strategies). The SLCPs account for much of current warming, and they must be dealt with.


The case where this matters most is natural gas, since natural gas is mostly methane, leaks at every point in the production and distribution process, but also releases CO2 when burned as a fuel. Methane is a whopping 86 times stronger at trapping heat than CO2 over a 20-year time scale, but “only” 34 times stronger over a 100-year time scale. And, as the IPCC wrote in its recent review of the science, “There is no scientific argument for selecting 100 years compared with other choices. The choice of time horizon is a value judgement since it depends on the relative weight assigned to effects at different times.”


The key point is that using natural gas to replace coal poses risks in all time periods. And, when you do the math based on actual observations of methane leakage, it turns out, as I’ve discussed, “By The Time Natural Gas Has A Net Climate Benefit You’ll Likely Be Dead And The Climate Ruined.”


As Sachs told MSNBC, “We have to move decisively” to carbon-free energy sources, including renewables and even nuclear. “This is pretty basic stuff.”


Here are more of Dr. Shindell’s thoughts on the subject:


I would strongly argue that there are two distinct environmental problems, one is long-term climate change for which CO2 is the dominant driver, and one is the combination of near-term climate change and air quality, for which SLCPs dominate. I don’t believe society is only capable of considering one problem at a time so that putting effort into cutting SLCPs would undermine efforts to cut CO2 — we consider multiple problems all the time (e.g. promoting clean water does not undermine promoting clean air, and there are countless such examples).


Demanding that CO2 reductions be made first, as has been promoted by some of the anti-SLCP crowd, runs the danger of blocking any action on SLCPs for many many years given the dismal state of progress on CO2. That would lead to many premature deaths that could have been prevented, larger near-term climate change that is already affecting people around the world, etc. So there are dangers either way if solving one problem is stalled due to the other, and so it’s important to keep working on both in my opinion. If our leadership can’t manage two environmental problems at once, then rather than choosing one or the other I’d say we should choose new leadership.


SLCP reductions don’t buy time for CO2 reductions, but they do provide more time for adaptation and improve the chances of avoiding tipping points by delaying the time at which we reach them so that if CO2 reductions take place they’ll have more time to have their impact.


Since Prof. Bob Howarth of Cornell has been remarkably prescient in raising concerns about methane leakage, I asked him to comment on Pierrehumbert’s findings:


1) It is a false choice to say we must rely on coal or natural gas. When I conclude the greenhouse gas footprint of natural gas is worse than that of coal on the decadal time scale, I am not arguing for coal. Rather, we should wean ourselves from all fossil fuels, and natural gas is not a bridge fuel towards doing so.


2) He ignores potential tipping points in the climate system which we increasingly run the risk of hitting if we do not reduce methane emissions. If the tipping points are hit, we will have runaway global warming that will be devastating. And we cannot avoid warming the planet to dangerously high temperatures (1.5 to 2 deg C) over the coming few decades by reducing carbon dioxide emissions. We must reduce methane emissions to lower this rate of warming on this time scale.


3) And yes, he ignores the problems with global climate disruption over the coming few decades, apparently feeling any damage on this time scale is OK if we are address the long-term problem.


I think I have done a good job of summarizing these issues and arguments in my May 2014 paper (Howarth, R. W. 2014. A bridge to nowhere: Methane emissions and the greenhouse gas footprint of natural gas.


UPDATE: Dr. Michael Tobis — climate blogger and modeler par excellence — points out that if we just reduce CO2 use sharply, then we would see a short-term boost in warming from the reduction in sulfate aerosols associated with the sharp coal reductions (see here). So that is yet another important reason we need to go after both coal and SLCPs.

U.S. Seen as Biggest Oil Producer After Overtaking Saudi Arabia

Posted by colin.hargreaves@aoc.org.au on July 10, 2014 at 1:35 AM Comments comments (0)

By Grant Smith, Bloomberg News

The U.S. will remain the world’s biggest oil producer this year after overtaking Saudi Arabia andRussia as extraction of energy from shale rock spurs the nation’s economic recovery, Bank of America Corp. said.

U.S. production of crude oil, along with liquids separated from natural gas, surpassed all other countries this year with daily output exceeding 11 million barrels in the first quarter, the bank said in a report today. The country became the world’s largest natural gas producer in 2010. TheInternational Energy Agency said in June that the U.S. was the biggest producer of oil and natural gas liquids.



U.S. oil output will surge to 13.1 million barrels a day in 2019 and plateau thereafter, according to the IEA, a Paris-based adviser to 29 nations. The country will lose its top-producer ranking at the start of the 2030s, the agency said in its World Energy Outlook in November.

IMF head says world must come to grips with climate change costs

Posted by colin.hargreaves@aoc.org.au on June 17, 2014 at 12:40 AM Comments comments (0)

CBC news, 10 June.

Christine Lagarde says don't wait for new targets, start carbon tax or other measures now.


"While Stephen Harper was congratulating Australian Prime Minister Tony Abbott yesterday for ending a carbon tax, the head of the IMF was in Montreal urging energy powerhouses like Canada to come to grips with the economics of climate change.


International Monetary Fund managing director Christine Lagarde urged economists and central bankers from around the world not to wait for the next round of climate change talks to take action to protect the environment.


All countries need to put mechanisms in place – whether a carbon tax or a cap and trade system – to pay for the effects of pollution, she said at the conference of the International Economic Forum of the Americas in Montreal. She urged countries not to wait for a new round of talks on global warming, but to start building these costs into their economic systems now."

Read More - http://www.cbc.ca/news/business/imf-head-says-world-must-come-to-grips-with-climate-change-costs-1.2670936

Obama unveils historic rules to reduce coal pollution by 30%

Posted by colin.hargreaves@aoc.org.au on June 2, 2014 at 7:05 PM Comments comments (0)

• New EPA rules spur prospects for deal to end climate change

• Climate groups welcome 'momentous development'

• Coal lobbyists say plans will create new US energy crisis

by Suzanne Goldenberg, Guardian, 2nd June 2014

The new rules represent the first time Obama has moved to regulate carbon pollution from power plants. Photograph: Matt Brown/AP

The Obama administration unveiled historic environment rules cutting carbon pollution from power plants by 30% on Monday, spurring prospects for a global deal to end climate change but setting up an epic battle over the environment in this year's mid-term elections.

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Why do next week's UN climate talks in Bonn matter?

Posted by colin.hargreaves@aoc.org.au on May 26, 2014 at 11:05 PM Comments comments (0)

by Liz Gallagher, rtcc.org

Few announcements expected, but meeting offers opportunity to build relationships ahead of Ban Ki-moon summit

Coming off the back of the Abu Dhabi Ascent, and the jubilation at the recently announced agreement in the Green Climate Fund (GCF) meeting, Bonn looks to be just another stage post en route to Paris in 2015.


But the Bonn intercessional this June is more than just a normal negotiation. Ministers have no sooner disembarked from their transportation out of the luxury oasis of the desert, to step back in it to reach the not so glamorous Maritim Hotel, Bonn.


The unusual suspects at the intercessional are the result of strong calls by the most vulnerable countries for Ministerial engagement to focus on raising ambition from now until 2020.


What this means in practice is two Ministerials: one for those who already have existing commitments through the Kyoto Protocol to provide details on how they could increase ambition; and one for everyone to demonstrate what actions they are taking pre-2020.


It is unlikely that this short window of opportunity will result in new announcements to increase pledges before 2020.


After all, the Climate Summit hosted by Ban Ki-moon is where Heads of State will come with ‘bold’ pledges; they’re not going to let their subordinates steal their thunder by announcing in June.


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CO2 concentrations top 400 parts per million throughout northern hemisphere

Posted by colin.hargreaves@aoc.org.au on May 26, 2014 at 9:15 PM Comments comments (0)

Press Release No 991, 26 May

Geneva, 26 May 2014 (WMO) - For the first time, monthly concentrations of carbon dioxide (CO2) in the atmosphere topped 400 parts per million (ppm) in April throughout the northern hemisphere. This threshold is of symbolic and scientific significance and reinforces evidence that the burning of fossil fuels and other human activities are responsible for the continuing increase in heat-trapping greenhouse gases warming our planet.


All the northern hemisphere monitoring stations forming the World Meteorological Organization (WMO) Global Atmosphere Watch network reported record atmospheric CO2 concentrations during the seasonal maximum. This occurs early in the northern hemisphere spring before vegetation growth absorbs CO2.


Whilst the spring maximum values in the northern hemisphere have already crossed the 400 ppm level, the global annual average CO2 concentration is set to cross this threshold in 2015 or 2016.


“This should serve as yet another wakeup call about the constantly rising levels of greenhouse gases which are driving climate change. If we are to preserve our planet for future generations, we need urgent action to curb new emissions of these heat trapping gases,” said WMO Secretary-General Michel Jarraud. “Time is running out.”


CO2 remains in the atmosphere for hundreds of years. Its lifespan in the oceans is even longer. It is the single most important greenhouse gas emitted by human activities. It was responsible for 85% of the increase in radiative forcing – the warming effect on our climate - over the decade 2002-2012.


Between 1990 and 2013 there was a 34% increase in radiative forcing because of greenhouse gases, according to the latest figures from the U.S. National Oceanic and Atmospheric Administration (NOAA).


According to WMO’s Greenhouse Gas Bulletin, the amount of CO2 in the atmosphere reached 393.1 parts per million in 2012, or 141% of the pre-industrial level of 278 parts per million. The amount of CO2 in the atmosphere has increased on average by 2 parts per million per year for the past 10 years.


Since 2012, all monitoring stations in the Arctic have recorded average monthly CO2 concentrations in spring above 400 ppm, according to data received from Global Atmosphere Watch stations in Canada, the United States of America, Norway and Finland.


This trend has now spread to observing stations at lower latitudes. WMO’s global observing stations in Cape Verde, Germany, Ireland, Japan, Spain (Tenerife) and Switzerland all reported monthly mean concentrations above 400 ppm in both March and April.


In April, the monthly mean concentration of carbon dioxide in the atmosphere passed 401.3 at Mauna Loa, Hawaii, according to NOAA. In 2013 this threshold was only passed on a couple of days. Mauna Loa is the oldest continuous CO2 atmospheric measurement station in the world (since 1958) and so is widely regarded as a benchmark site in the Global Atmosphere Watch.


The northern hemisphere has more anthropogenic sources of CO2 than the southern hemisphere. The biosphere also controls the seasonal cycle. The seasonal minimum of CO2 is in summer, when substantial uptake by plants takes place. The winter-spring peak is due to the lack of biospheric uptake, and increased sources related to decomposition of organic material, as well as anthropogenic emissions. The most pronounced seasonal cycle is therefore in the far north.


The WMO Global Atmosphere Watch coordinates observations of CO2 and other heat-trapping gases like methane and nitrous oxide in the atmosphere to ensure that measurements around the world are standardized and can be compared to each other. The network spans more than 50 countries including stations high in the Alps, Andes and Himalayas, as well as in the Arctic, Antarctic and in the far South Pacific. All stations are situated in unpolluted locations, although some are more influenced by the biosphere and anthropogenic sources (linked to human activities) than others.


The monthly mean concentrations are calculated on the basis of continuous measurements. There are about 130 stations that measure CO2 worldwide.

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Alaska wildfire burns 250 square miles, 1,000 buildings evacuated

Posted by colin.hargreaves@aoc.org.au on May 26, 2014 at 3:50 PM Comments comments (0)

Reuters, 26 May

A spreading Alaskan wildfire has forced the evacuation of about 1,000 buildings but firefighters have gained ground by containing about 30 percent of the wind-driven blaze, a U.S. Forest Service spokesman said on Monday.

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Pontifical Statement on Sustainability

Posted by colin.hargreaves@aoc.org.au on May 24, 2014 at 11:30 PM Comments comments (0)

Statement of the Joint PAS/PASS Workshop on Sustainable Humanity, Sustainable Nature: Our Responsibility

Stabilizing the Climate and Giving Energy Access to All with an Inclusive Economy

Humanity has entered a new era. Our technological prowess has brought humanity to a crossroads. We are the inheritors of two centuries of remarkable waves of technological change: steam power, railroads, the telegraph, electrification, automotive transport, aviation, industrial chemistry, modern medicine, computing, and now the digital revolution, biotechnologies and nanotechnologies. These advances have reshaped the world economy into one that is increasingly urban and globally connected, but also more and more unequal.

However, just as humanity confronted “Revolutionary Change” (Rerum Novarum) in the Age of Industrialization in the 19th century, today we have changed our natural environment to such an extent that scientists are redefining the current period as the Age of the Anthropocene, that is to say an age when human action, through the use of fossil fuels, is having a decisive impact on the planet. If current trends continue, this century will witness unprecedented climate changes and ecosystem destruction that will severely impact us all.

Human action which is not respectful of nature becomes a boomerang for human beings that creates inequality and extends what Pope Francis has termed “the globalization of indifference” and the “economy of exclusion” (Evangelii Gaudium), which themselves endanger solidarity with present and future generations.

The advances in measured productivity in all sectors – agriculture, industry and services – enable us to envision the end of poverty, the sharing of prosperity, and the further extensions of life spans. However, unfair social structures (Evangelii Gaudium) have become obstacles to an appropriate and sustainable organization of production and a fair distribution of its fruits, which are both necessary to achieve those goals. Humanity’s relationship with nature is riddled with unaccounted for consequences of the actions each of us take for both present and future generations. Socio-environmental processes are not self-correcting. Market forces alone, bereft of ethics and collective action, cannot solve the intertwined crises of poverty, exclusion, and the environment. However, the failure of the market has been accompanied by the failure of institutions, which have not always aimed at the common good.

Problems have been exacerbated by the fact that economic activity is currently measured solely in terms of Gross Domestic Product (GDP) and therefore does not record the degradation of Earth that accompanies it nor the abject inequalities between countries and within each country. The growth in GDP has been accompanied by unacceptable gaps between the rich and the poor, who still have no access to most of the advancement of the Era. For example, about fifty-percent of available energy is accessed by just one billion people, yet the negative impacts on the environment are being felt by the three billion who have no access to that energy. Three billion have so little access to modern energy that they are forced to cook, heat and light their homes with methods dangerous to their health.

The massive fossil fuel use at the heart of the global energy system deeply disrupts the Earth’s climate and acidifies the world’s oceans. The warming and associated extreme weather will reach unprecedented levels in our children’s life times and 40% of the world’s poor, who have a minimal role in generating global pollution, are likely to suffer the most. Industrial-scale agricultural practices are transforming landscapes around the world, disrupting ecosystems and threatening the diversity and survival of species on a planetary scale. Yet even with the unprecedented scale and intensity of land use, food insecurity still stalks the planet, with one billion people suffering from chronic hunger and another billion or so suffering from the hidden hunger of micronutrient deficiencies. Tragically, a third of the produced food is wasted, which as Pope Francis said is “like stealing from the table of the poor and the hungry”.

In view of the persistence of poverty, the widening of economic and social inequalities, and the continued destruction of the environment, the world’s governments called for the adoption by 2015 of new universal goals, to be called Sustainable Development Goals (SDGs), to guide planetary-scale actions after 2015. To achieve these goals will require global cooperation, technological innovations that are within reach, and supportive economic and social policies at the national and regional levels, such as the taxation and regulation of environmental abuses, limits to the enormous power of transnational corporations and a fair redistribution of wealth. It has become abundantly clear that Humanity’s relationship with Nature needs to be undertaken by cooperative, collective action at all levels – local, regional, and global.

The technological and operational bases for a true sustainable development are available or within reach. Extreme poverty can be ended through targeted investments in sustainable energy access, education, health, housing, social infrastructure and livelihoods for the poor. Social inequalities can be reduced through the defense of human rights, the rule of law, participatory democracy, universal access to public services, the recognition of personal dignity, a significant improvement in the effectiveness of fiscal and social policies, an ethical finance reform, large scale decent work creation policies, integration of the informal and popular economic sectors, and national and international collaboration to eradicate the new forms of slavery such as forced labor and sexual exploitation. Energy systems can be made much more efficient and much less dependent on coal, petrol and natural gas to avoid climate change, protect the oceans, and clean the air of coal-based pollutants. Food production can be made far more fruitful and less wasteful of land and water, more respectful of peasants and indigenous people and less polluting. Food wastage can be cut significantly, with both social and ecological benefits.

Perhaps the greatest challenge lies in the sphere of human values. The main obstacles to achieving sustainability and human inclusion are inequality, unfairness, corruption and human trafficking. Our economies, our democracies, our societies and our cultures pay a high price for the growing gap between the rich and the poor within and between nations. And perhaps the most deleterious aspect of the widening income and wealth gap in so many countries is that it is deepening inequality of opportunity. Most importantly, inequality, global injustice, and corruption are undermining our ethical values, personal dignity and human rights. We need, above all, to change our convictions and attitudes, and combat the globalization of indifference with its culture of waste and idolatry of money. We should insist upon the preferential option for the poor; strengthen the family and community; and honor and protect Creation as humanity’s imperative responsibility to future generations. We have the innovative and technological capability to be good stewards of Creation. Humanity needs urgently to redirect our relationship with nature by adopting the Sustainable Development Goals so as to promote a sustainable pattern of economic development and social inclusion. A human ecology that is healthy in terms of ethical virtues contributes to the achievement of sustainable nature and a balanced environment. Today we need a relationship of mutual benefit: true values should permeate the economy and respect for Creation should promote human dignity and wellbeing.These are matters on which all religions and individuals of goodwill can agree.

These are matters that today’s young people around the world will embrace, as a way to shape a better world. Our message is one of urgent warning, for the dangers of the Anthropocene are real and the injustice of globalization of indifference is serious. Yet our message is also one of hope and joy. A healthier, safer, more just, more prosperous, and sustainable world is within reach. The believers among us ask the Lord to give us all our daily bread, which is food for the body and the spirit.


PASS President Prof. Margaret Archer

Prof. Vanderlei S. Bagnato

Prof. Antonio M. Battro

Dr. Lorenzo Borghese

Prof. María Verónica Brasesco

Prof. Joachim von Braun

Prof. Edith Brown Weiss

Dr. Pablo Canziani

Marco Casazza

Prof. Paul Crutzen

Aisha Dasgupta

Prof. Sir Partha Dasgupta

Prof. Gretchen Daily

Prof. Pierpaolo Donati

Prof. Gérard-François Dumont

Prof. Ombretta Fumagalli Carulli

Juan Grabois

Prof. Allen Hertzke

Prof. Vittorio Hösle

Prof. Daniel Kammen

Emily Kelly

Prof. Charles Kennel

Dr. Anil Kulkarni

Prof. Yuan T. Lee

Prof. Pierre Léna

Prof. M. Ramón Llamas

Prof. Karl-Göran Mäler

Dr. Marcia McNutt

Prof. Dr. Jürgen Mittelstrass

Prof. Walter Munk

Prof. Naomi Oreskes

Alicia Peressutti

Dr. Janice Perlman

Prof. Vittorio Possenti

Prof. Ingo Potrykus

Prof. V. Ramanathan

Prof. Sir Martin J. Rees

Dr. Daniel Richter

Prof. Ignacio Rodríguez-Iturbe

Prof. Louis Sabourin

Prof. Jeffrey Sachs

Msgr. Marcelo Sánchez Sorondo

Prof. Bob Scholes

Matthew Siegfried

Prof. Hanna Suchocka

Prof. Govind Swarup

Msgr. Mario Toso

Prof. Rafael Vicuña

Prof. Peter Wadhams

Prof. Dr. Hans F. Zacher

Prof. Stefano Zamagni