Planetary boundaries is a concept of nine Earth system processes qui-have boundaries Proposed 2009 by a group of Earth system and environmental scientistsled by Johan Rockström from the Stockholm Resilience Center and Will Steffen from the Australian National University . The group wants to define a „safe operating space for humanity“ for the international community, including governments at all levels, international organizations, the civil society, the scientific community and the private sector , as a precondition for sustainable development . The framework is based on scientific evidenceIndustrial Revolution hasbecome the main driver of global environmental change. The scientists assert That ounce human activity HAS Passed some Thresholds gold tipping point, defined as „planetary boundaries“, there is a risk of „irreversible and abrupt environmental change“. [3] The nine Earth system processes boundaries mark the safe area for the As of 2017, two boundaries have already been crossed, while others are in imminent danger of being crossed. [4]

History of framework

In 2009 a group of Earth system and environmental scientists led by Johan Rockström from the Stockholm Resilience Center and Will Steffen from the Australian National University collaborated with 26 leading academics, including Nobel laureate Paul Crutzen , Goddard Institute for Space Studies James Hansen climate scientist and the German Chancellor ’s chief climate adviser Hans Joachim Schellnhuberand identified nine „planetary life support systems“ essential for human survival, attempting to quantify how far seven of these systems had been driven. They estimated how much more humans can go before planetary habitability is threatened. [1] Estimates indicated that three of these boundaries- climate change , biodiversity loss, and the biogeochemical flow boundary-appear to have been crossed. The boundaries were „rough, first estimates only, surrounded by large uncertainties and knowledge gaps“ which interact in complex ways that are not yet well understood. Boundaries are defined to help define a „safe space for human development“,on the planet. [1] The 2009 report [1] was presented to the General Assembly of the Club of Rome in Amsterdam. [5] An edited summary of the article was published in the 2009 edition of Nature . [6] Nobel laureate Mario J. Molina and biologist Cristián Samper . [7]

In 2015, the paper was published in Science to update the Planetary Boundaries concept [2] and findings were presented at the World Economic Forum in Davos, January 2015.

Background

The idea

The idea that our planet has limits, with the burden of the world, has been around for some time. In 1972, The Limits to Growth was published. It presented a model in qui five variables: world population , industrialization, pollution, food production and resources depletion , are Examined, and regarded to Grow Exponentially , whereas the Ability of Technology pour augmenter resources availability is only linear . [8] Subsequently, the report was widely dismissed, particularly by economists and businessmen, [9] and it has been claimed that history has proved to be incorrect. [10]In 2008, Graham Turner from the Commonwealth Scientific and Industrial Research Organization (CSIRO) published „A comparison of the Limits to Growth with thirty years of reality“. [11] Turner found that the observed historical data from 1970 to 2000 closely matches the simulated results of the „standard run“ limits of growth model for almost all the reported outputs. „The comparison is well within uncertainty bounds of both the magnitude and the trends over time.“ [11] Turner also reviewed a number of reports, particularly by economists, which discusses the limits of discrediting the limits-to-growth model. Turner says these reports are flawed, and reflect misunderstandings about the model.[11] In 2010, Nørgård, Peet and Ragnarsdóttir referred to the book as „pioneering report“, and said that „withstood the test of time and, indeed, has only become more relevant.“ [12]

With few exceptions, economics and discipline have been dominated by a perception of living in an unrestricted world, where resource and pollution problems have been solved by moving resources or people to other parts. The very hint of limitation Any overall did suggéré in the postponement The Limits to Growth Was starts with disbelief and rejection by businesses and MOST Economists. However, this finding was mostly based on false premises.

– Meyer & Nørgård (2010) .

Our Common Future [13] was published in 1987 by United Nations‘ World Commission on Environment and Development . It is trying to recapture the spirit of the Stockholm Conference . Its aim is to interlock the concepts of development and environment for future political discussions. It introduced the famous definition for sustainable development :

„Development that meets the needs of the present without compromising the ability of future generations to meet their own needs.“

-  Brundtland Report 1987

Of a different kind is the approach made by James Lovelock . In the 1970s he and microbiologist Lynn Margulis presented the Gaia theory or hypothesis , that states that all organisms and their inorganic surroundings are integrated into a single self-regulating system. [14] The system has the ability to react to disruptions or deviations, a homeostasis). Nevertheless, this capacity has limits. For instance, when a living organism is subjected to a temperature that is lower than its living range, it can be used for its adjustment. Similarly the Earth may be able to react to large deviations in critical parameters. In his book The Revenge of Gaia , he asserts that the destruction of rainforests and biodiversity, compounded with the increase of greenhouse gases by humans, is producing global warming .

From Holocene to Anthropocene

Main article: Anthropocene
Our planet’s ability to provide an environment for our country. The environment-our life-support system-is changing rapidly from the stable Holocene state of the last 12,000 years, during which we developed agriculture, villages, cities, and contemporary civilizations, to an unknown future state of significantly different conditions.

– Steffen, Rockström & Costanza (2011)

The Holocene started about 10,000 years ago. It is the current interglacial period, and it is a relatively stable environment of the Earth. There have been natural environmental fluctuations during the Holocene, but the key atmospheric and biogeochemical parameters have been relatively stable. [15] This stability and resiliencehas allowed agriculture to develop and complex societies to thrive. [16] According to Rockström et al., we „have now become so dependent on one another, and how we have organized society, technologies, and economies around them, which we must take into account. point for a desirable planetary state. “ [1]

Since the industrial revolution , according to Paul Crutzen , Will Steffen and others, the planet has entered a new epoch, the Anthropocene . In the Anthropocene, humans have become the agents of change to the Earth system. [17] There has been some evidence of ozone depletion. [18] However, other biophysical procedures are also important. [19] For example, since the advent of the Anthropocene, the rate at which species is being extinguished has increased over 100 times, [20] and humans are now driving the driving force altering global rivers flows [21].Water flows from the land surface. [22] Continuing pressure on the Earth’s biophysical systems from the point of view of further degradation and the possibility of further degradation. It is difficult to address the issue, because the predominant paradigms of social and economic development are largely indifferent to the looming possibilities of large scale environmental disasters triggered by humans. [23] [24] Legal boundaries can help keep human activities in check, but they are only as effective as the political will to make and enforce them. [25]

Nine boundaries

Thresholds and boundaries

The threshold , or climatological tipping point , is the value for which a very small increment for the control variable (like CO 2 ) produces a large, possibly catastrophic, change in response variable (global warming).

The threshold is difficult to locate, because the Earth System is very complex. Instead of defining the threshold value, the study establishes a range, and the threshold is supposed to lie inside it. The lower end of this range is defined as the boundary . Therefore, it defines a safe space, in the sense that we are below the boundary, we are below the threshold value. If the boundary is crossed, we enter into a danger zone. [1]

Planetary Boundaries [26]
Earth-system process Variable Control [27] Boundary
value
Current
value
Boundary crossed Preindustrial
value
Commentary
1. Climate change Atmospheric Carbon Dioxide Concentration ( ppm by volume) [28]

See also: Tipping point (climatology)
350
400
yes
280
[29]
Alternatively: Increase in radiative forcing (W / m 2 ) since the beginning of the industrial revolution (~ 1750)
1.0
1.5
yes
0
[30]
2. Biodiversity loss Extinction rate (number of species per million per year)
10
> 100
yes
0.1-1
[31]
3. Biogeochemical (a) Anthropogenic nitrogen removed from the atmosphere (millions of tonnes per year)
35
121
yes
0
[32]
(b) anthropogenic phosphorus going into the oceans (millions of tonnes per year)
11
8.5-9.5
No.
-1
[33]
4. Ocean acidification Global mean saturation state of aragonite in surface seawater (omega units)
2.75
2.90
No.
3.44
[34]
5. Land use Land area converted to cropland (percent)
15
11.7
No.
low
[35]
6. Freshwater Global human consumption of water (km 3 / yr)
4000
2600
No.
415
[36]
7. Ozone depletion Stratospheric ozone concentration ( Dobson units )
276
283
No.
290
[37]
8. Atmospheric aerosols Overall particulate concentration in the atmosphere, on a regional basis
not yet quantified
[38]
9. Chemical pollution Concentration of toxic substances , plastics , endocrine disruptors , heavy metals , and radioactive contamination into the environment
not yet quantified
[39]

The Proposed Framework lays the groundwork for shifting approach to governance and management, away from the Essentially sectoral analyzes of limits to growth at avocation Minimizing negative externalities , Toward the estimate of the safe space for human development. Planetary boundaries define, as it was, the boundaries of the „planetary playing field“ for humanity if major human-induced environmental change on a global scale is to be avoided

Transgressing one or more planetary boundaries may be highly damaging or even catastrophic, due to the risk of crossing thresholds that trigger non-linear, abrupt environmental changes within continental – to planetary-scale systems. The 2009 study identified nine planetary boundaries and, drawing on current scientific understanding, the proposed quantifications for seven of them. These seven are climate change ( CO 2 concentration in the atmosphere <350 ppm and / or a maximum change of +1 W / m 2 in radiative forcing ); ocean acidification (mean surface seawater saturation state with respect to aragonite ≥ 80% of pre- industrial levels);stratospheric ozone (less than 5% reduction in total atmospheric O 3 from a pre-industrial level of 290 Dobson Units ); biogeochemical nitrogen (N) cycle (limiting industrial and agricultural fixation of N 2 to 35 Tg N / yr) and phosphorus (P) cycle (annual P inflow to oceans not to exceed 10 times the natural background weathering of P); global freshwater use (<4000 km 3/ yr of consumptive use of runoff resources); land system change (<15% of the ice-free land surface under cropland); and the rate at which biological diversity is lost (annual rate of <10 extinctions per million species). The two additional planetary boundaries for loading and unloading .

Debate

On the framework

From the Stockholm Memorandum
Science indicates that we are transgressing planetary boundaries that have kept civilization safe for the past 10,000 years. Evidence is growing that human pressures are starting to overwhelm the Earth’s buffering capacity. Humans are now the most significant driver of global change , propelling the planet into a new geological epoch, the Anthropocene . We can not longer exclude the possibility that our collective actions will trigger tipping points, abrupt risking and irreversible consequences for human communities and ecological systems.

– Stockholm Memorandum (2011)

The framework has been drawing strong responses from scientists and advisors.

Christopher Field , director of the Carnegie Institution’s Department of Global Ecology , is impressed: „This is a work that is critically important.“ [40] But the conservation biologist Stuart Pimm is not impressed: „I do not think this is a way of thinking about things … The notion of a single boundary is just devoid of serious content. extinction rate 10 times the background rate acceptable? “ [40] and the environmental policy analyst Bill Clarkthinks: „Tipping points in the earth system are dense, unpredictable … and unlikely to be avoidable by early warning indicators. It follows that … ’safe operating spaces‘ and ‚planetary boundaries‘ are thus highly suspect and potentially ‚opiates‘. “ [41]

The biogeochemist William Schlesinger queries whether thresholds are a good idea for pollution at all. He thinks we are going to wait for you. „Management based on thresholds, attractive in its simplicity, allows pernicious, slow and diffuse degradation to persist nearly indefinitely.“ [42]

The hydrologist David Molden thinks planetary boundaries are a welcome new approach in the ‚limits to growth‘ debate. „As a scientific organizing principle, the concept has many strengths […] the numbers are important because they provide targets for policymakers, giving a clear indication of the magnitude and direction of change. They also provide benchmarks and direction for science. As we improve our understanding of Earth processes and complex inter-relationships, these benchmarks can and will be updated […] we now have a tool we can use to help us think more deeply—and urgently—about planetary limits and the critical actions we have to take.“[43]

The ocean chemist Peter Brewer queries whether it is „truly useful to create a list of environmental limits without serious plans for how they may be achieved […] they may become just another stick to beat citizens with. Disruption of the global nitrogen cycle is one clear example: it is likely that a large fraction of people on Earth would not be alive today without the artificial production of fertilizer. How can such ethical and economic issues be matched with a simple call to set limits? […] food is not optional.“[44]

The environment advisor Steve Bass says the „description of planetary boundaries is a sound idea. We need to know how to live within the unusually stable conditions of our present Holocene period and not do anything that causes irreversible environmental change […] Their paper has profound implications for future governance systems, offering some of the ‚wiring‘ needed to link governance of national and global economies with governance of the environment and natural resources. The planetary boundaries concept should enable policymakers to understand more clearly that, like human rights and representative government, environmental change knows no borders.“[45]

The climate change policy advisor Adele Morris thinks that price-based policies are also needed to avoid political and economic thresholds. „Staying within a ’safe operating space‘ will require staying within all the relevant boundaries, including the electorate’s willingness to pay.“[46]

In summary, the planetary boundary concept is a very important one, and its proposal should now be followed by discussions of the connections between the various boundaries and of their association with other concepts such as the ‚limits to growth‘. Importantly, this novel concept highlights the risk of reaching thresholds or tipping points for non-linear or abrupt changes in Earth-system processes. As such, it can help society to reach the agreements required for dealing effectively with existing global environmental threats, such as climate change.

– Nobel laureate Mario J. Molina[47]

In their report (2012) entitled „Resilient People, Resilient Planet: A future worth choosing,“ The High-level Panel on Global Sustainability called for bold global efforts, „including launching a major global scientific initiative, to strengthen the interface between science and policy. We must define, through science, what scientists refer to as “planetary boundaries”, “environmental thresholds” and “tipping points”.“[48]

In 2011, at their second meeting, the High-level Panel on Global Sustainability[49] of the United Nations had incorporated the concept of planetary boundaries into their framework, stating that their goal was: „To eradicate poverty and reduce inequality, make growth inclusive, and production and consumption more sustainable while combating climate change and respecting the range of other planetary boundaries.“[50]

Elsewhere in their proceedings, panel members have expressed reservations about the political effectiveness of using the concept of „planetary boundaries“ : „Planetary boundaries are still an evolving concept that should be used with caution […] The planetary boundaries question can be divisive as it can be perceived as a tool of the “North” to tell the “South” not to follow the resource intensive and environmentally destructive development pathway that rich countries took themselves… This language is unacceptable to most of the developing countries as they fear that an emphasis on boundaries would place unacceptable brakes on poor countries.“[51]

However, the concept is routinely used in the proceedings of the United Nations,[52] and in the UN Daily News. For example, the UNEP Executive Director Achim Steiner states that the challenge of agriculture is to „feed a growing global population without pushing humanity’s footprint beyond planetary boundaries.“[53] The United Nations Environment Programme (UNEP) Yearbook 2010 also repeated Rockström’s message, conceptually linking it with ecosystem management and environmental governance indicators.[54]

The planetary boundaries concept est used in proceedings by the European Commission , [55] and Was Referred to in the European Environment Agency synthesis report The European environment – state and outlook 2010 . [56]

On the boundaries

They are debate about which boundaries are most relevant, and which way they can be usedfully quantified.

Climate change

The black line shows the atmospheric carbon dioxide concentration for the period 1880-2008. Red bars show the temperatures above and below the average temperature. Year-to-year temperature fluctuations are due to natural processes, Such As the effects of El Niño , La Niña , and the eruption of volcanoes wide. [57]

Radiative forcing is a measure of the difference between the incoming radiation energy and the outgoing radiation energy acting across the boundary of the earth. Positive radiative forcing results in warming. From the start of the industrial revolution in 1750 to 2005, the increase in atmospheric carbon dioxide has a positive effect on radiative forcing, averaging about 1.66 W / m². [58]

The climate scientist Myles Allen thinks setting „a limit on long-term atmospheric carbon dioxide concentrations -measures of the much more immediate challenge of limiting warming to 2 ° C.“ He says that the concentration of carbon dioxide is not a variable control, and that it is more important than the temperature of warming. [30]

Adele Morris, Policy Director, Climate and Energy Economics Project, Brookings Institution , makes a critique of the economic-political point of view. She puts emphasis on choosing policies that minimize costs and preserve consensus. She favors a system of green-house gas emissions , and emissions trading , as well as global warming. She thinks that too-ambitious objectives, like the boundary limit on CO 2 , may discourage such actions. [46]

Biodiversity loss

According to the biologist Cristián Samper , a „boundary that expresses the probability of families of species disappearing over time would better reflect our potential impacts on the future of life on Earth.“ [59]

The conservation ecologist Gretchen Daily claims that „it is time to confront the hard truth that traditional approaches to conservation, taken alone, are doomed to fail. a tiny fraction of Earth’s biodiversity The challenge is to make conservation from economic and cultural perspectives We can not go on treating nature like an all-you-can-eat buffet. stability, seafood, timber, and other biological and physical services. A few pioneers are integrating conservation and human development.China is investing $ 100 billion in „ecocompensation,“ including innovative policy and funding mechanisms that reward conservation and restoration. The country is also creating ecosystem function conservation areas that make up 18 percent of its land area. Colombia and South Africa have made dramatic policy changes, too. Three advances would help the rest of the world scale such models of success. One: new science and tools for value and account for natural capital, in biophysical, economic and other terms […] Two: compelling demonstrations of such tools in resource policy. Three: cooperation among governments, development organizations, corporations and communities to help nations build more sustainable economies while also maintaining critical ecosystem services. “ [60]

Nitrogen cycle

Since the industrial revolution, the Earth’s nitrogen cycle has been disturbed even more than the carbon cycle. „Human activities“ terrestrial biosphere. “ [61] Only a small part of the fertilizer applied in agriculture is used by plants. Most of the nitrogen and phosphorus ends up in rivers, lakes and the sea, where stress stresses aquatic ecosystems. For example, fertilizer which discharges from rivers in the Gulf of Mexico has damaged shrimp fisheries because of hypoxia. [61]

The biogeochemist William Schlesinger thinks we are just waiting for somebody else . He says the boundary suggested for phosphorus is not sustainable, and would have been known to phosphorus reserves in less than 200 years. [42]

Robert Howarth says: „Human activity has greatly increased the incidence of fossil fuels in the world. such as the Northeastern US Emissions from Emissions from Emissions from Emissions from In this case, it is possible for the plant to be reduced to a large extent, to be reduced, to the extent that it is predicted that the Clean Air Act and its amendments are required to comply;These plants pollute far out of proportion to the amount of electricity they produce.

In agriculture, many farmers could use less fertilizer, and the reductions in crop yields would be small or nonexistent. Runoff from cornfields is particularly preventable because of its roots. In addition, nitrogen losses can be reduced by 30 percent or more, such as rye or wheat, which can help the soil. These crops also increase carbon sequestration in soils, mitigating climate change. Better yet is to grow perennial plants such as fat rather than corn; nitrogen losses are many times lower. Nitrogen pollution from concentrated animal feeding operations (CAFOs) is a huge problem.

As recently as the 1970s, most animals were fed local crops, and the animals were returned to the fields as fertilizer. Today, most animals are fed to the world, making it „uneconomical“ to return the manure. The solution? Require CAFO owners to treat their wastes, just as cities must do with human wastes. Further, if we ate less meat, we would need to generate more animal fertilizer. Eating meat from animals that are range-fed on perennial grasses would be ideal. The explosive growth in the production of ethanol as biofuel is greatly aggravating nitrogen pollution. Several studies have suggested that if mandated US ethanol targets are met, the amount of nitrogen flowing down the Mississippi Riverand fueling the Gulf of Mexico dead zone may increase by 30 to 40 percent. The best alternative would be to forgo the production of ethanol from corn. If the country wants to rely on biofuels, it should instead grow fat and trees and burn these to co-generate heat and electricity; nitrogen pollution and greenhouse gas emissions would be much lower. “ [62]

Phosphorus

Further information: Peak phosphorus

With regard to phosphorus, the ocean engineer David Vaccari says that the most sustainable environmental flow of phosphorus „would be the natural flux: seven million metric tons per year (Mt/yr). To hit that mark yet satisfy our usage of 22 Mt/yr, we would have to recycle or reuse 72 percent of our phosphorus […] The flow could be reduced with existing technologies… [lowering] the loss to waterways from 22 to 8.25 Mt/yr, not very much above the natural flux.“[63]

Peak phosphorus is a concept to describe the point in time at which the maximum global phosphorus production rate is reached. Phosphorus is a scarce finite resource on earth and means of production other than mining are unavailable because of its non-gaseous environmental cycle.[64] According to some researchers, Earth’s phosphorus reserves are expected to be completely depleted in 50–100 years and peak phosphorus to be reached in approximately 2030.[65][66]

Estimated change in sea surface pH from the pre-industrial period (1700s) to the present day (1990s). Δ pH is in standard pH units.[67]

Ocean acidification

Surface ocean acidity has increased thirty percent since the industrial revolution. About one quarter of the additional carbon dioxide generated by humans is dissolved in the oceans, where it forms carbonic acid. This acidity inhibits the ability of corals, shellfish and plankton to build shells and skeletons. Knock-on effects could have serious consequences for fish stocks. This boundary is clearly interconnected with the climate change boundaries, since the concentration of carbon dioxide in the atmosphere is also the underlying control variable for the ocean acidification boundary.[61]

The ocean chemist Peter Brewer thinks „ocean acidification has impacts other than simple changes in pH, and these may need boundaries too.“[44]

The marine chemist Scott Doney thinks „the main tactics are raising energy efficiency, switching to renewable and nuclear power, protecting forests and exploring carbon sequestration technologies. Regionally, nutrient runoff to coastal waters not only creates dead zones but also amplifies acidification. The excess nutrients cause more phytoplankton to grow, and as they die the added CO2 from their decay acidifies the water. We have to be smarter about how we fertilize fields and lawns and treat livestock manure and sewage […] Locally, acidic water could be buffered with limestone or chemical bases produced electrochemically from seawater and rocks. More practical may be protecting specific shellfish beds and aquaculture fisheries. Larval mollusks such as clams and oysters appear to be more susceptible to acidification than adults, and recycling old clamshells into the mud may help buffer pH and provide better substrate for larval attachment. The drop in ocean pH is expected to accelerate in coming decades, so marine ecosystems will have to adapt. We can enhance their chances for success by reducing other insults such as water pollution and overfishing, making them better able to withstand some acidification while we transition away from a fossil-fuel energy economy.“[68]

Land use

Across the planet, forests, wetlands and other vegetation types are being converted to agricultural and other land uses, impacting freshwater, carbon and other cycles, and reducing biodiversity.[61]

The environment advisor Steve Bass says research tells us that „the sustainability of land use depends less on percentages and more on other factors. For example, the environmental impact of 15 per cent coverage by intensively farmed cropland in large blocks will be significantly different from that of 15 per cent of land farmed in more sustainable ways, integrated into the landscape. The boundary of 15 per cent land-use change is, in practice, a premature policy guideline that dilutes the authors‘ overall scientific proposition. Instead, the authors might want to consider a limit on soil degradation or soil loss. This would be a more valid and useful indicator of the state of terrestrial health.“[69]

The Earth systems scientist Eric Lambin thinks that „intensive agriculture should be concentrated on land that has the best potential for high-yield crops […] We can avoid losing the best agricultural land by controlling land degradation, freshwater depletion and urban sprawl. This step will require zoning and the adoption of more efficient agricultural practices, especially in developing countries. The need for farmland can be lessened, too, by decreasing waste along the food distribution chain, encouraging slower population growth, ensuring more equitable food distribution worldwide and significantly reducing meat consumption in rich countries.“[70]

Freshwater

Human pressures on global freshwater systems are having dramatic effects . The freshwater cycle is another very important issue. [61] Freshwater resources, Such As lakes and aquifers , are usually naturally renewable resources qui recharge (the term fossil water is used to describe Sometimes qui aquifers do not recharge). Overexploitation occurs when the resource is reloaded. Refreshing usually comes from areas of streams, rivers and lakes. Forests enhance the recharge of local aquifers, a major source of aquifer depletion. [72] Depleted aquifers can become polluted with contaminants such as nitrates , or permanently damaged by subsidence or through saline intrusion from the ocean. This turns much of the world’s underground water and lakes into finite resources with peak usage debates similar to oil . [73] Though Hubbert’s original analysis is not applicable to renewable resources, their overexploitation can result in a Hubbert-like peak . A modified Hubbert curve applies to any resource that can be harvested faster than it can be replaced. [71]

The hydrologist Peter Gleick comments: „Few rational Observers deny the need for boundaries to freshwater use More controversial is defining Where Those limits are or what steps to take to constrain Ourselves Within Them Another way to describe thesis boundaries is the concept of.. Peak water. Three different ideas are useful. ‚Peak renewable‘ water limits are the total renewable flows in a watershed. Many of the world’s major rivers are already approaching this threshold when evaporation and consumption surpasses natural replenishment of precipitation and other sources. ‚Peak nonrenewable‘, where, in Great Lakes, Libya, India, northern China and parts of California’s Central Valley. „Ecological ecological“ is an important factor in the estimation of the hydrological system, which is considered to be of greater ecological importance than that of additional ecological destruction. Although it is difficult to quantify this point accurately, We have clearly passed the point of […] The good news is that the potential for savings, without hurting human health or economic productivity, is vast. Improvements in water-use efficiency are possible in every sector. More can be grown with less water (and less water contamination) by shifting from irrigation to drip and precision sprinklers, along with more accurate monitoring and managing soil moisture. Conventional power plants can change from water cooling to dry cooling, and more energy can be generated by these sources. without hurting human health or economic productivity, is vast. Improvements in water-use efficiency are possible in every sector. More can be grown with less water (and less water contamination) by shifting from irrigation to drip and precision sprinklers, along with more accurate monitoring and managing soil moisture. Conventional power plants can change from water cooling to dry cooling, and more energy can be generated by these sources. without hurting human health or economic productivity, is vast. Improvements in water-use efficiency are possible in every sector. More can be grown with less water (and less water contamination) by shifting from irrigation to drip and precision sprinklers, along with more accurate monitoring and managing soil moisture. Conventional power plants can change from water cooling to dry cooling, and more energy can be generated by these sources. along with more accurate monitoring and managing soil moisture. Conventional power plants can change from water cooling to dry cooling, and more energy can be generated by these sources. along with more accurate monitoring and managing soil moisture. Conventional power plants can change from water cooling to dry cooling, and more energy can be generated by these sources.[74]

The hydrologist David Molden says „a global limit on water consumption is necessary, but the suggested planetary boundary of 4,000 cubic kilometers per year is too generous.“ [43]

Ozone depletion

The stratospheric ozone layer protectively filters ultraviolet radiation (UV) from the Sun , which would otherwise damage biological systems. The actions taken after the Montreal Protocolappeared to be keeping the planet within a safe boundary. [61] However, in 2011, according to a paper published in Nature , the boundary was unexpectedly pushed into the Arctic ; „Dobson units (DU) are typically near zero, but reached nearly 45%“. [75]

The Nobel laureate in chemistry, Mario Molina , says „it is a reasonable limit for acceptable ozone depletion, but it does not represent a tipping point“. [47]

The physicist David Fahey says that a result of the Montreal Protocol „stratospheric ozone depletion will largely reverse by 2100. The gain has relied, in part, on intermediate substitutes, particularly hydrochlorofluorocarbons (HCFCs), and the growing use of compounds that cause no depletion, such as hydrofluorocarbons (HFCs).

  • „Continue to check the ozone layer to ensure that the HCFC phase will not be complete until 2030.
  • „Maintain the Scientific Assessment Panel under the Protocol.
  • „Maintain the Technology and Economic Assessment Panel.“ It provides information on technologies and substitutes for ozone-depleting substances.

Climate change affects ozone depletion by chemical composition and dynamics of the stratosphere, and compounds such as HCFCs and HFCs are caused by gases. for HFCs could significantly contribute to climate change. “ [76]

Atmospheric Aerosols

Aerosol particles in the atmosphere impact the health of humans and the influence of monsoon and global atmospheric circulation systems. Some aerosols produce clouds which cool the Earth by reflecting sunlight back to space, while others, like soot, produce thin clouds in the upper stratosphere which behave like a greenhouse, warming the Earth. We balance, anthropogenic aerosols probably produce a net negative radiative forcing (cooling influence). [77] Worldwide each year, aerosol particles result in about 800,000 premature deaths. Aerosol is not included in the scope of the planetary boundaries, but it is not yet [78]

Chemical pollution

Some chemicals, such as persistent organic pollutants , heavy metals and radionuclides , have potentially irreversible additive and synergistic effects on biological organisms, reducing fertility and resulting in permanent genetic damage . Sublethal uptakes are drastically reduced marine and mammal populations. This boundary seems important, but it is hard to quantify. [61]

A Bayesian emulator for persistent organic pollutants has been developed which can be used to quantify the boundaries for chemical pollution. [79] To date, important exposures of polychlorinated biphenyls (PCBs) to which have been proposed as a chemical pollution planetary boundary. [80]

Interaction among boundaries

The boundary values ​​are more likely to be in place than others. However, a planetary boundary may interact in a different way. Rockström et al. 2009 did not analyze such interactions, but they suggest that many of these interactions will reduce rather than expand the proposed boundaries.

For example, the land use boundary could be used, and it could be used for agriculture. At a regional level, water resources may decline in Asia if continued deforestation in the Amazon . Such considerations suggest the need for „extreme caution in approaching or transgressing any individual planetary boundaries.“ [1]

Another example with coral reefs and marine ecosystems . In 2009, De’Ath, Lough & Fabricius (2009) showed that, since 1990, calcification in the reefs of the Great Barrier has decreased significantly over the last 400 years (14% in less than 20 years). Their evidence que la Suggests Increasing temperature stress and the Declining ocean saturation state of aragonite is making it difficulty for reef corals to deposit calcium carbonate. Bellwood & others (2004)explored how multiple stressors, such as increased nutrient loads and fishing pressure .Guinotte & Fabry (2008) showed that ocean acidification will significantly change the distribution of marine life, particularly species „that build skeletons, shells, and tests of biogenic calcium carbonate.“ Increasing temperatures, UV radiation levels ocean acidity all stress marine biota , and the combination of these stresses may well cause disturbances in the abundance and diversity of marine biological systems that the effects of a single stressor acting alone. “ [81]

Subsequent developments

The concept of planetary boundaries is a limitless or infinitely substitutable. It threatens the business-as-usual approach to economic growth. The fact that reference to planetary boundaries was excluded from the [ Rio + 20] conference statement is a counterintuitive sign that the concept is being taken very seriously and has gained traction. Had planetary boundaries remained in the statement, the most credible interpretation is that they would join a growing list of nice-sounding goals that are included but never achieved in the end. Planetary boundaries will not go away. The intrinsic limits to the amount of resources and environmental services that can not be removed from the Earth System can not be eliminated by wishful thinking, denial, or omission from official sustainable development conference statements. It is simply the nature of the planet we inhabit.

– Will Steffen [82]

The donut

In 2012 Kate Raworth from Oxfam noted the Rockstrom concept does not take human population growth into account. [83] She suggests social boundaries should be incorporated into the planetary boundary structure, such as jobs, education, food, access to water, health services and energy and to accommodate an environment that is compatible with poverty eradication and „rights for all“. Within the framework of the equation, it is limited to a certain area where there is a „safe and just space for humanity to thrive in“. [84]

Tenth boundary

In 2012, Steven Running suggests a tenth boundary, the annual net primary production of all terrestrial plants , as an easily determinable measure of integrating variables that would give „a clear signal about the health of ecosystems“. [85] [86] [87]

United Nations endorsement

The United Nations Secretary-General Ban Ki-moon endorsed the concept of planetary boundaries on 16 March 2012, when he presented the key points of the report of his High Level Panel on Global Sustainability to an informal plenary of the UN General Assembly. [84] [88] Ban stated: „The Panel’s vision is to eradicate poverty and reduce inequality, to make growth more inclusive and more sustainable, while [89] The concept was incorporated into the so-called „zero draft“ of the outcome of the United Nations Conference on Sustainable Development in Rio de Janeiro 20-22 June 2012.[90] However, the use of the concept is more likely to be the subject of discussion, „it is also important to note that The reason for this is that the idea is simply too much adopted, and it is necessary to be challenged, weathered and tested at a level of robustness. [91]

The planetary boundary framework was updated in 2015. [2] It was suggested that three of the boundaries could be used. These strongly influence the remaining boundaries. In the paper, the framework is made to make it more applicable to the regional scale.

Agricultural and nutritional impacts

Environmental impacts of agriculture and nutrition in the framework of planetary boundaries according to Meier (2017) [92]

Human activities related to agriculture and nutrition globally contribute to the transgression of four planetary boundaries. Surplus nutrient flows (N, P) are of highest importance, followed by excessive land-system change and biodiversity loss. In the case of biodiversity loss, P cycle and land-system change, the transgression is in the zone of uncertainty – indicating an increasing risk (yellow circle in the figure), the N boundary related to agriculture is more than 200% transgressed – indicating a high risk (red marked circle in the figure). [92]

Other commentary

  • Anderies JM, Carpenter SR, Steffen W, Rockstrom J (2012) „The Topology of Global Non-Linear Carbon Dynamics: From Tipping Points to Planetary Boundaries“ Center for the Study of Institutional Diversity, Working Paper Series # CSID-2012-009.
  • Barnosky AD, Hadly EA and 19 others (2012) „Approaching a state shift in Earth’s biosphere“ Nature , 486 : 52-58. doi : 10.1038 / nature11018
  • Biermann, Frank (2012). „Planetary boundaries and earth system governance: Exploring the links“. Ecological Economics . 81 : 4-9. doi : 10.1016 / j.ecolecon.2012.02.016 .
  • Blomqvist L, Nordhaus T and Shellenberger M (2012) „The planetary boundaries hypothesis: A review of the evidence“, The Breakthrough Institute – an environmental policy think tank.
  • Brook BW, Ellis EC, MP Perring, Mackay AW and Blomqvist L (2013) „Does the terrestrial biosphere have planetary tipping points?“ Trends in Ecology & Evolution . doi : 10.1016 / j.tree.2013.01.016 Commentary .
  • Cornell, Sarah (2012). „On the System Properties of the Planetary Boundaries“ . Ecology and Society . 17 (1): r2. doi : 10.5751 / ES-04731-1701r02 . Responses
  • Galaz, Victor (2012). „Environment: Planetary boundaries concept is valuable“ . Nature . 486 (7402): 191. doi : 10.1038 / 486191c . PMID  22699598 .
  • Galaz, V; Biermann, F; Folke, C; Nilsson, M; Olsson, P (2012). „Global environmental governance and planetary boundaries: an introduction“. Ecological Economics . 81 : 1-3. doi : 10.1016 / j.ecolecon.2012.02.023 .
  • Leach, M., J. Rockström, P. Raskin, I. Scoones, AC Stirling, A. Smith, J. Thompson, E. Millstone, A. Ely, E. Arond, C. Folke, and P. Olsson (2012). ) „Transforming Innovation for Sustainability“ Ecology and Society , 17 (2): 11. doi : 10.5751 / ES-04933-170211 . Responses
  • Lewis, Simon L (2012). „We must set planetary boundaries wisely“ . Nature . 485 : 417. doi : 10.1038 / 485417a . PMID  22622531 .
  • Lovejoy T (2012) The Greatest Challenge of Our New York Times Species , Opinion, 5 April 2012.
  • Rockström, Johan and Klum, Mattias (2012) The Human Quest: Prospering Within Planetary Boundaries Princeton University Press. ISBN  978-91-87007-14-9 (hardcover), ISBN  978-91-87173-25-7 (ebook). Review
  • Whiteman G, Walker B, Perego P (2012) „Planetary Boundaries: Ecological Foundations for Corporate Sustainability“Wiley Online Library Journal of Management
  • Is Earth Nearing an Environmental „Tipping Point“? Scientific American , 7 June 2012.
  • Walking the line Scientific American , 13 June 2012.
  • Boundary conditions: The idea of ​​planet-wide environmental boundaries, beyond which humanity would be at its peril, is gaining ground The Economist , 16 June 2012.
  • Human Life Dependent on ‚Planetary Boundaries‘ That Should Not Be Crossed , Sixty-seventh session of the United Nations General Assembly , Second Committee Discussion Panel, GA / EF / 3341, October 2012.
  • Agriculture’s hunger for nitrogen Oversteps planetary boundaries The Conversation , 5 November 2012.
  • Griggs, D; Stafford-Smith, M .; Gaffney, O; Rockström, J; Öhman, MC; Shyamsundar, P; Steffen, W; Glaser, G; et al. (2013). „Sustainable development goals for people and planet“ (PDF) . Nature . 495 : 305-307. doi : 10.1038 / 495305a .
  • Leach, Melissa (2013) Democracy in the Anthropocene? Science and Sustainable Development Goals at the UNHuffington Post , March 27, 2013.
  • Pielke, Roger (2013) Planetary Boundaries as Political Power Grab The Energy Collective , 7 April 2013.
  • Worldwatch Institute (1913) State of the World 2013: Is Sustainability Still Possible? Island Press. ISBN  9781610914499. Review