It sounds like the stuff of science fiction: the creation, using balloons or jets, of a manmade atmospheric sunshade to shield the most vulnerable countries in the global south against the worst effects of global warming.
But amid mounting interest in “solar geoengineering” – not least among western universities – a group of scientists from developing countries has issued a forceful call to have a greater say in the direction of research into climate change, arguing that their countries are the ones with most at stake.
Scientists have long known that manmade events like pollution in the atmosphere, smoke from forest fires and volcanic eruptions can create a cooling effect.
That has led scientists at Harvard University to propose their own experiment, which they call “stratospheric controlled perturbation effect”, or SCoPEx for short. It involves using a balloon to test the controversial proposition that aerosols released at a height of 20km in the Earth’s atmosphere can alter the reflective properties of cloud cover.
Now a dozen scholars, from countries including Bangladesh, Brazil, China, Ethiopia, India, Jamaica and Thailand, have joined the debate, arguing in the journal Nature that poor countries should take a lead in the field since they have most to gain or lose from the technology.
The cooling effect has long been known in phenomena such as “ship tracks” – narrow artificial clouds of pollution, created by emissions from ships, that contain more and smaller water droplets than typical clouds, making them brighter and more reflective of sunlight.
“Solar geoengineering – injecting aerosol particles into the stratosphere to reflect away a little inbound sunlight – is being discussed as a way to cool the planet, fast,” the scientists write in Nature.
“Solar geoengineering is outlandish and unsettling. It invokes technologies that are redolent of science fiction – jets lacing the stratosphere with sunlight-blocking particles, and fleets of ships spraying seawater into low-lying clouds to make them whiter and brighter to reflect sunlight.
“Yet, if such approaches could be realised technically and politically, they could slow, stop or even reverse the rise in global temperatures within one or two years.
In an interview with Reuters, Dr Atiq Rahman, director of the Bangladesh Centre for Advanced Studies and the article’s lead author, amplified his arguments.“The technique is controversial, and rightly so,” they add. “It is too early to know what its effects would be: it could be very helpful or very harmful. Developing countries have most to gain or lose. In our view, they must maintain their climate leadership and play a central part in research and discussions around solar geoengineering.”
“Clearly [solar radiation management geoengineering] could be dangerous, but we need to know whether, for countries like Bangladesh, it would be more or less risky than passing the 1.5C warming goal. This matters greatly to people from developing countries and our voices need to be heard.
“The overall idea [of solar geoengineering] is pretty crazy, but it is gradually taking root in the world of research,” said Rahman.
The solar geoengineering studies may be helped by a new $400,000 (£284,100) research project, the solar radiation management governance initiative (SRMGI), which is issuing a first call for scientists to apply for finance this week.
The initiative is financed by the Open Philanthropy Project, a foundation backed by Dustin Moskovitz, a co-founder of Facebook, and his wife, Cari Tuna.
The fund could help scientists in developing nations study the regional impacts of solar geoengineering, for instance on droughts, floods or monsoons, said Andy Parker, a co-author and project director of the SRMGI.
Rahman said the academics were not taking sides about whether geoengineering would work.
And not everyone is convinced by the prospect of the technology.
In a leaked draft of a report about global warming due for publication in October, a UN panel of climate experts express scepticism about solar geoengineering, suggesting it may be “economically, socially and institutionally infeasible”.
Liyuan Zhang
ReplyDeleteThis article is quite attractive for me as it suggests alternative ways to encounter the global warming effect with method such as solar geoengineering. That is to say, there are proposition that works to reflect sunlight and thus reducing global warming. And in addition, there are ways such as spraying a number of reflective chemicals and compounds into the atmosphere so as to cool down the temperature.
It then leads to the question of whether we shall seek this technological approach to save us with an unlimited greenhouse gas emission or the emission of the greenhouse gas shall be prohibited in the first place so as to alleviate the global warming effect.
From what the article has suggested, there are possibility that the global warming effect could actually be slowed down or even solved completely if technology and politics permits. And in this way, there is no worrying about the previous and current greenhouse gas emission. However, there are obstacles for these approaches to be fully taken into effect due to the political and technological reasons. Technologically speaking, these approaches can be dangerous to implement. Politically speaking, the need between developed and developing countries differed.
As far as I am concerned, the idea of the artificial and low-flying cloud is quite promising as it could literally cool down the temperature with exactly similar water content to real cloud. However, still people may fear the consequences brought by it. Personally, I think we should do these experiments to work out the alternative solutions and understand the logic and science behind the environmental issues. We could try to reduce greenhouse gas emission in the first place, yet still we need to do research to look for ways to make the environment better for sustainable development of all species.
In the recent conference held at Harvard University, it was mentioned that these scientists plan to be involved developing new methods and experiments (as mentioned in the article above). MIT published a review in response to Harvard's efforts which stated, “They would be among the earliest official geo-engineering related experiments conducted outside of a controlled laboratory or computer model, underscoring the growing sense of urgency among scientists to begin seriously studying the possibility as the threat of climate change mounts.” Geo-engineering is seemingly just coming into mainstream science, however has been around for quite a few decades now rendering MIT's statement quite untrue. For instance, the 2008 Olympics held in China utilized the same geo-engineering technology to create ideal weather for the games. I've personally been interested in the field of geo-engineering and have considered targeting my career in that direction on and off for years now. There are many controversial components that go along with it, along with many agendas. The United States government actually has a section where they comment upon geoengineering and climate modification/mitigation from the United States Senate Committee on Commerce, Science and Transportation in November 1978, which states: “In addition to specific research programs sponsored by Federal agencies, there are other functions related to weather modification which are performed in several places in the executive branch. Various federal advisory panels and committees and their staffs – established to conduct in-depth studies and prepare comprehensive reports, to provide advice or recommendations, or to coordinate Federal weather modification programs – have been housed and supported within executive departments, agencies, or offices.” (via https://archive.org/stream/weatificat00unit#page/n1/mode/2up)
ReplyDeleteThis said, it isn't a question of if the science would work but how it would actually impact life on planet Earth, or how it's already impacting it. There has compelling research done by many scientists on the affects of geosynthesised substances on organismal life. An interesting article from Current Science scientific journal investigates this affect on human life in India. (https://www.researchgate.net/publication/281927862_Aluminum_poisoning_of_humanity_and_Earth's_biota_by_clandestine_geoengineering_activity_Implications_for_India) The article reviews previous research that discusses the detection of heavy metals (aluminum, barium, etc.) in rainwater, fly ash, etc. from a multitude of samples across the globe. What was found was that there were very high concentrations of heavy metals throughout 77% of all samples and that there is no way that any natural phenomenon could have caused it. Within these areas there were found to be a heavy influx of people being diagnosed with neurological conditions, clearly correlating geosynthesised substances with the diagnoses.
The chairman of Carbon engineering at Harvard University, David W. Keith has always been involved with geo-engineering technology and has done several works in regards to the technology, assessment, as well as policy related to geo-engineering. He commented on some of the findings of his research saying, "You may end up killing many ten’s of thousands of people a year as a direct results of that decision" in regards to heavy metal toxicity.
In essence, I believe geo-engineering could solve some problems if used correctly, but cause many others as well. It's a fairly controversial field because of government interactions but very interesting from a scientific standpoint. I think it is possible to engineer synthetic chemicals that efficiently infrare particles causing the green house affect without them being so harmful to life on earth, especially if combined with an overall reduction in GHG emissions.
Another interesting report to be looked at that's relative to this topic: "Weather as a Force Multiplier; Owning the Weather in 2025" from 1996. (http://csat.au.af.mil/2025/volume3/vol3ch15.pdf)
ReplyDeleteSolar geoengineering is a concept that has been around since the 1960s. It is only now that the topic is becoming relevant again due to the potential benefits that may come with solar geoengineering. While this concept is continuing to gain support by agencies such as the Environmental Defense Fund and Natural Resources Defense Council, we still need more research and development before we can try to start implementing these methods.
ReplyDeleteThe idea of creating an artificial cloud to reflect Sunlight seems like something that would come out of a movie. However, as we continue to gain knowledge and research on this topic, it seems that this method might actually be feasible. However, as stated under the picture, I feel that it is more resourceful to limit GHG emissions from the start rather than coming up with expensive ways to prevent them, not even guaranteed. This just leads to a poor allocation of wasted resources.
Moving forward, in order for something like this to work, all parties must be on the same page. Although the benefits/risks sem most prevalent to developing nations, it is important that all nations climb aboard the movement. However, as stated in the UN panel, solar geoengineering may be 'economically, socially and institutionally infeasbile.' This means that regardless of what happens, this may just be a fairytale concept that is impossible to implement into today's current society.
As stated in the article linked to the Guardian, even if the world cut GHG to zero, we would still face the side effects of global warming for decades to come. The implementation of these reflective clouds could start cooling immediately. However, we cannot trust computer models, we must continue to conduct research and experiments in order to fully understand this concept of solar geoengineering. And determine if it is actually feasible to implement it into our global society.
Nicholas Arciszewski
This idea of solar geoengineering is fascinating. Although it seems crazy, and maybe even impossible right now, I believe that nothing can be discredited until it is tried. Even if there is a risk associated with this technology, there is a risk in not trying it as well. The rising temperatures are something that are far from our minds here in the northeast of the United States, as we dream of the warmer temperatures. However; in other parts of the world these issues are extremely pressing. It is very true that poorer nations have much more to loose in this case, and therefore they should have a say in the way research and development of solar geoengineering is conducted. Countries that have the means to conduct the research typically have more power in these debates, but it is important to consider who has more at stake and to take their opinions seriously as well. Putting more financial support into this research sounds like the only option in my mind, because it cannot be ruled out until it is given a fair chance. If this could be the solution to significant environmental damage, everything should be done to see if it is possible. As stated in the post, there is no denying that it could be dangerous and potentially pose a threat, but it needs to be weighed against the alternative.
ReplyDeleteLingyi Meng
ReplyDeleteWith the risk associated with global warming that has been a worldwide concern, scientists have done numerous research on possible solutions. Solar geoengineering is among the technology that has proved to have an answer for global warming threat. This technique involves reflecting away little inbound sunlight through injecting aerosol particles into the atmosphere in an attempt to cool the planet. The technology thus creates a humanmade atmospheric sunshade to shield the earth against worsening effects of global warming. Jets and fleets of ships are used to carry out this practice. Jets laces the atmosphere with sunlight-blocking particles while the vessel sprays low-lying clouds with sea water making them whiter and brighter for sunlight reflection. According to research, the realization of this technique has a potential of reducing the rising global temperature within few years.
Solar Geoengineering has its roots from different occurring events. Scientist found out that humanmade events such as atmospheric pollution, smoke from forest fires and volcanic eruption cause cooling effects. Furthermore, it was also revealed that emissions from ships contained more and- smaller water droplets than typical clouds hence made the clouds brighter and more reflective of sunlight. Such incidents could have propelled the researchers into coming up with the solar geoengineering technology.
Several Types of research have been conducted to investigate the viability and potential effects of solar geoengineering. Some used balloon to test the controversy that releasing aerosols in the earth’s atmosphere at the height of 20k could alter the reflective property of the cloud cover. Although this technique proves to be very helpful, its effects are yet to be revealed. Some suggest that solar geoengineering could be either very helpful or very harmful. Others feel that this technique could be economical, socially, and institutionally infeasible. However, Open Philanthropy Project has financed initiative aimed at studying regional impacts of solar geoengineering.
The idea of spraying certain types of particles into the stratosphere that could potentially help reflect more heat back into space is cool to think about. Scientists believe it could work because nature already does it. Large volcanic eruptions in the past have blasted tens of millions of tons of sulfur dioxide into the sky, which contributed to lower global temperatures in subsequent months. However, what’s not clear is how precisely the technique could control worldwide temperatures, what materials would work best, and what the environmental side effects might be. While geoengineering would keep global temperatures and costs low, previous volcanic eruptions have decreased precipitation levels in parts of the world, and sulfur dioxide is known to deplete the protective ozone layer. It would also not contribute to reversing ocean acidification. Since geoengineering doesn’t solve ocean acidification, we would still be dealing with droughts and famines. In my opinion, I believe geoengineering should only be used as an emergency scenario. Although I see the benefits of it, we shouldn’t rely on it as a solution. I think it is too risky since it might be doing more harm than good.
ReplyDeleteDeShawn McLeod
ReplyDeleteI can understand why there would be ethical issues regarding the technology of solar engineering. My biggest concern is what happens if the technology doesn’t have regulations on it and it’s completely owned by private parties. What would that mean for the American public?
Considering that second– and third-world countries are affected more with economic disaster, like the Great Recession, I’m unsure if their global standing will collapse without the help they need in order to thrive.
The history of Western settlers ravaging and taking resources and power from, now, second– and third-world countries, I think it’s unlikely that Western countries will help those that need it if the global climate-change technology dramatically shifted. Recently, China has been loaning second- and third-world countries funds in order to advance while China owns a part of their country. I’m interested to see how second- and third-world countries will improve in spite of global disadvantage they’re in.
I’m also interested in the politics around technology like this. It seems like it would be a dangerous game because climate change technology would inevitably be used in times of conflict and war. It’s almost scary to think how much this technology will harm and progress the human population.
I have read about this potential solution before and to me, it is a scary and potentially harmful idea. Humans have manipulated nature since the beginning of time. However, it is our excessive manipulation that has gotten us into this problem to being with. In order to solve the problems we have caused, we simply want to manipulate nature even further. This is not smart and does not solve the core of the problem: we are consuming and emitting too much in order to keep our economies growing. Instead of trying to solve the problem by potentially doing more harm, I believe it is essential to to lower our emissions and transition to a sustainable and renewable energy based economy.
ReplyDeleteThe idea of solar geoengineering is quite fascinating and terrifying at the same time. Being able to spray millions of particles into the sky which will ultimately reflect the sun’s rays and cool Earth seems like a great idea, but at the same time what if this method of solar geoengineering disrupts the atmosphere of the Earth even more? This disruption can further change the weather while causing harmful side effects to those living on the Earth.
ReplyDeleteIn my opinion, there are different ways to change and affect this climate change that is taking place. There is a moral hazard behind this idea of solar geoengineering, by this I mean that instead of trying to directly tackle the causes behind the climate change, which are lessening the use of fossil fuels, which is a known fact that will ultimately help to reduce the climate, humans choose to resort to solar geoengineering where the end product is unknown. This unknown end product can have the largest effect on developing countries since they have the most to gain or the most to lose. The social geoengineering can help to lower global temperatures which could help to reduce the harmful effects of climate change, like higher temperatures, changes to rainfall patterns and stronger tropical cyclones.
This concept of solar geoengineering ultimately can be the answer to preventing the climate change that is happening on Earth. There is much to lose and much to gain while on the journey of understanding how exactly this concept will function. There can be harmful effects, but that is the risk in trying to achieve sustainability of the planet. If one does not try, one will never know.
Yang Peidong
ReplyDeleteIn light of the rapidly growing concentration of carbon dioxide, and the increasingly serious global warning, scientist turn their focus on a new technology-solar engineering. Solar engineering mimics the nature of volcanic eruptions. People inject sulfate aerosols into the stratosphere to block sunlight and cool Earth. Despite its assumed function to reverse the global warning, this technology still has many risks.
Firstly, the control of such technology will cause ethical issue, and even chaos in the world. The greatest challenges to the successful deployment of geoengineering may be the social, ethical, and political issues associated with governance (John Shepherd, 2009). At present, developed countries like UK, US, and Europe are exploring solar engineering, and they have the most profound knowledge in this field. But developing countries are the most vulnerable to climate changes. Any measure taken by these developed countries to change climate will greatly influence developing countries. Thus, developed countries should invite developing countries to attend this program and most such research should be based out of the US, the European Union, and the UK.
Secondly, it will damage plants. Solar engineering reduces the sunlight radiation that reaches the Earth surface through artificial aerosols. But as for plants, sunlight is of great importance, which support their lives and growth. With the reduction of sunlight, plants on earth will definitely decrease their growth rate, and disrupt ecological system. What’s more, crops that we are fed on also will lower harvest, resulting in a global famine. Thus, scientists need to assess risks to crops and other vegetation when they explore the solar engineering at the same time.
Thirdly, commercial control or military use of this solar technology. When solar engineering is completely explored, who can own it and what if it is controlled by some terrorist or anti-government organization. To solve the commercial control, we can establish a public organization to manage it, or let the UN to control takeover it. But military use is a trickier problem than the commercial control, because it is hard to ensure that such technology won’t be stolen by immoral people.
In my opinion, preventing the demission of carbon dioxide and exploring new environmental-friendly approach are the most feasible for our future.
Reference:
Shepherd, J. G. (2009). Geoengineering the climate: science, governance and uncertainty. Royal Society.
Solar geoengineering is an approach to reduce the impacts of climate change by reflecting a small amount of inbound sunlight back out into space. What spurred this idea was back in 1991, when a volcano erupted in the Philippines, shooting particles into the air that temporarily cooled the planet by reflecting some solar energy. From the above article and multiple other published content, solar geoengineering seems like a solid idea to combat climate change. An added bonus is that this process is CHEAP; so cheap researchers at Harvard say an individual government could implement it. But, many scientists and the UN have stated that it could be dangerous and have negative effects that have not been studied thoroughly enough. For instance, what kind of effect would solar geoengineering have on our biodiversity and ecosystems? This instant change caused by geoengineering could affect the way that organisms have begun to adapt and therefore result in issues with the ecosystem. Another issue is that many researchers state this method is a “quick fix” and does not represent a long lasting plan. Once we start solar geoengineering, it can never be ignored and could become costlier as time and complexity builds up. It also ignores the source of our emissions, and could present a false hope. If we can reflect some of the solar energy back into space and experience almost instant results of cooler temperatures, we may lose the incentives we have built to start limiting our emission levels. This could lead to ignorance for many industries and businesses that have begun taking the steps at changing their means of production to cut emissions.
ReplyDeleteUltimately, it seems that this method is too good to be true and will have repercussions that will contradict all that we have worked for thus far in combatting climate change. As many have said, it is a seemingly good idea that lacks the necessary research and facts on its effects. Since the UN has stepped in to say that solar geoengineering may be “economically, socially, and institutionally infeasible”, it is likely this idea will not be gaining much traction or implemented anytime soon.
The question that is raised at the beginning of the article about which path to take, emit green house gases then conduct expensive experiments in an attempt to clean it up, or limit emissions in the first place, seems like an obvious answer. Logically it would make more sense to limit emissions right of the bat in order to prevent unnecessary and costly work. It seems as though we are currently in the state of trying to do both, limit emissions while trying to clean up the mess that has already been made. Countries are setting personal goals and are all working towards sustainable practices and economic growth. Wouldn’t it be counter productive to focus energy and money on ways to clean the air rather than ways to reduce or quit the varieties of pollution from the beginning. The fact that Solar geoengineering is defined as “injecting aerosol particles into the stratosphere” proves that it is in some ways another artificial substance that could potentially cause more harm than good. Though it is an uneasy thought, more human interaction and violations with nature, the possible benefits are remarkable, which is what makes solar geoengineering worthwhile. The possible economic growth for developing countries makes this idea humor able, for now. However, the big picture proves a large investment of time and money, with a reward that we are currently unable to predict. In terms of sustainably combating climate change, this option may be feasible, but not without high risk and potential failure including increased pollution, decreased biodiversity, and economic hardships worldwide.
ReplyDeletePersonally I have never heard of this proposal before, but shortly after reading this article I already have many concerns. Scientists are obviously exploring new methods that could help alleviate the negative externalities of climate change and slow its progression, but geo-engineering man-made clouds to shield us from the sun's rays seems a little sketchy. As the blog/article stated, there would need to be experiments conducted before anything was released into the atmosphere; looking at our history with messing with the checks and balances of nature, I don't think this is a good idea at all. Even if the experiments come back with a positive outcome, we can't know for sure that it wouldn't have a negative consequence in the long run. I also believe that this is a quick fix to climate change. Why spend millions of dollars on this project when nothing will change unless our habits change? This quick fix is a step in the wrong direction because it lowers the incentive to keep changing our consumption patterns. I think the money is better off being spent on sustainable energy, the production of eco-friendly materials, and clean up. With that being said, if this project were to be conducted, what would happen to our wildlife without the usual amount of sunlight? Without necessary sunlight, our wildlife will suffer and so will we. Ultimately this plan has too many "ifs" to be considered safe or sustainable.
ReplyDelete
ReplyDeleteDaniella Antolino
I have heard and read articles about this proposal before. It is a very controversial topic as well as risky. For these developing countries we need to pan out if this experiment would be more harmful or helpful. Scientists have been working to eliminate or decrease green house gases. Solar engineering seems to be a challenging subject, there can be many harmful effects that cannot be reversible once these experiments take place. We are running out of time to figure out solutions to decrease pollution and protection from the sun. So the solar engineering may not be a terrible thing to try in these developing countries.
injecting aerosol particles into the stratosphere to reflect away a little inbound sunlight is being discussed as a way to cool the planet fast, but for the plants and environments that need that source of light It can be harmful or damaging to those. Will reflecting the sunlight away affect the plants? it can be more damaging to them. That is another factor that the scientists have to take into account.
But when it comes to climate sustainability this is option may be feasible due to the amount of damages humans put on the environment, the radiation is only going to get worse and temperature are going to rise so this is definitely an experiment even though has risks might be worth the try. We need to start something we need to see some changes, so even though this is a controversial topic and there are many issues to this experiment it could be a success. The temperatures In Bangladesh, Brazil, China, Ethiopia, India, and Jamaica can be altered and have stability in the future. I am excited to learn and see more articles discussing this process and see how it plays out.
Xin Jiang
ReplyDeleteGeoengineering, a process used to change the Earth's climate and make Earth more suitable for human habitation. Although current experts have proposed many feasible solutions, the implementation of each method faces enormous challenges in all aspects. The completion of these programs requires precise cooperation between each country on Earth. This is an unfinished feat.
More importantly, scientists still have differences in the safety of geoengineering. Due to the large number of variables affecting the Earth's climate system, any solution may cause unpredictable side effects. Scientists have generated so many arguments for this.
However, the proposal to use Earth Engineering to change the earth remains strong. Many scientists insist on the geoengineering strategy as the last straw to save the future of humanity.
To make any decisions related to climate change, whether it is related to geoengineering or reducing emissions, the human side of the process is basically the same: we need to work together to achieve a willingness to work together. Even if a miraculous geoengineering technology emerges tomorrow, it can ensure that we can help us recover to the pre-industrial climate without any side effects, and everyone needs to be tested and implemented together.
Therefore, the question of progress may not be the lack of scientific research funding or political issues - it is just that we can hardly reach consensus. This may be more challenging than the scientific puzzle, and it is also a problem that has existed since human beings. However, in order to avoid the worst, we must overcome it!
The concept of solar geoengineering seems like a great solution to trying to reverse climate change in theory. But, this just seems like a rabbit-hole idea that will lead to countries not considering climate change as seriously as it needs to be taken. As a species humans have had such a negative impact on the environment, so I am skeptical that this would solve how greenhouse gases affect the atmosphere. Instead of emitting more gases and particles into the atmosphere, maybe we should just stop emitting so many greenhouse gases and take the money that is being used on all of these tests to invest in clean, renewable energy sources. If we rely on patterns that already exist - ex. the sun rises and photovoltaic cells convert sunlight to electricity - we may be in a better place when trying to repair the world.
ReplyDeleteIn addition, how can scientists be sure these artificial clouds would remain in place? Do the particles dissipate in air, having to be constantly emitted into the atmosphere? Both of those pose serious risks with consequences that will affect the rest of the world, regardless of where this initiative is implemented.
I believe scientists representing developing countries should be more included in the climate change conversation, though. International politics is so dominated by a colonial mindset that decisions made without the rest of the world do not always help the rest of the world. The idea that decisions are being made for communities without their input in itself is colonial. We’ve seen how colonial decisions negatively impact countries - for example, in the Middle East after the fall of the Ottoman Empire up until today. Colonialism is responsible for the divide between “Developing countries” and “Developed countries”, and why we even have these debates today.
Mark Shkreli
ReplyDeleteThe topic of geoengineering our climate is controversial in my opinion, especially if you consider how some feel it may be more harmful than hurtful. Personally I have never been too into science to have a valid reason to choose a side. But my biggest fear is that by using science to try and disrupt the balance of our climate and "try" to make it better may influence some to think in only one direction. Case and point what was said in the end about how an expert from the UN Reports shows that the idea would be infeasible in more than one way. It seems like the first steps to this topic, a balloon used to measure aerosol effects at a certain height (20km). I believe Dr. Rahman has a good insight on it. When he discusses the topic he shows signs of multiple perspectives on it, like how it could be helpful, but while at the same time harmful. I believe that the best way to take a side is after looking at it from multiple perspectives so I would like to see more about Dr. Rahman's opinion on geoengineering. As for myself I cannot take a side but I do feel that maybe it is a little too risky to try and execute now, I feel more research needs to be done.