The action of surface water and groundwater in the chemical weathering or chemical erosion of soluble carbonate rocks such as magnesium carbonates (dolomites) and calcium carbonates (limestone) produces landforms that are called karst topography.
Geological features such as caves, sinkholes, underground rivers, barren and rocky ground and lack of surface water bodies are all results of the chemical processes of karst topography. The ontology of the term derives from its original reference to the Karst region in Slovenia, a limestone region near the Gulf of Trieste (Encyclopaedia Britannica).
Karst topography characteristically occurs when a layer of carbonate rocks occur just below surface soil, whose dissolution sometimes causes surface soil to funnel in, sometimes suddenly without warning.
The trigger for a collapse, Dr. Anthony Cooper, a geologist with the British Geological Survey claims, most commonly occurs due to changes in groundwater levels, or a sudden increase in levels of surface water.
In dry spells, when the water table is reduced, the withdrawal of groundwater levels leaves cavities once filled by water and silt might lead to a weakening of soil foundations. Also additions to the weights placed on surface soil or heavy downpours coupled with soil subsidence might also trigger a sinkhole.
As about 10 per cent of the Earth’s surface is comprised of karst topographies, it is not uncommon to find sinkholes. In fact the entire state of Florida in the US is classified as a karst landscape, such that insurance is a legal obligation for insurers to home owners.
The famous eroded cliffs at the western Irish coast, the caves in Slovenia, the 662 meter deep Xiaozhai tiankeng sinkhole in China, the 612 meter deep sinkhole Dashiwei tiankeng in China, the 530 meter deep Red Lake in Croatia, the 510 meter deep Minye sinkhole in Papua New Guinea and the Sotano Del Barro (410 meters) and the Sotano de las Golondrinas (372 meters) sinkholes in Mexico are some of the most significant examples of karst topographies (Jon Henley, 2013).
In India karst topography is present in the Vindhya region (mainly southwestern Bihar), the Himalayas (parts of Jammu & Kashmir, Robert Cave, Sahasradhara, the eastern Himalayas, areas near Dehradun), Pachmarhi in Madhya Pradesh, the surrounding coast near Vishakhapatnam, and Bastar in Chhattisgarh. It is reported that the 2004 tsunami originating near the Andaman and Nicobar islands might have caused sinkholes to appear all over certain islands of the Nicobar island group. Three Nicobar islands are particularly affected – Campbell Bay, Car Nicobar and Kamorta.
Sinkhole Mitigation
Mitigation measures for sinkholes basically bear the precautionary goals of filling sinkholes, maintenance of groundwater levels and checking contamination of groundwater, preventing surface water drainage into risk zones, and maintaining safety standards at risk zones . There are various approaches depending on the nature of the risk zone and the surrounding topography, land use and the climate.
The highest priority is provided to drainage in areas having karst topography and the approach is based on geological and engineering assistance that is site specific. Due attention is provided both to surface and ground water. It is necessary that inspections of risk areas take place on a regular basis, especially after major rain events. The fostering of vegetative buffer zones also works to prevent excessive run off of surface water, although it is advisable to plant native plant breeds and avoid the propagation of noxious plants and weeds.
Soil can also be investigated for assessing culpability of bearing karst features. Traditional methods such as boring soil and rock, and also percussion methods necessitates penetrating the ground in order to extract information on the underground geological properties of soil.
The invasiveness of these methods when dealing with the problem of sinkholes has led to a turn towards technological non-invasive methods for determining the properties of suspect soil. Some of these non-invasive methods include ground penetrating radar, resistivity imaging, seismic surveying and microgravity surveying. These on-site assessments are the necessary pre-requisite for engineering and development processes in suspect karst topographies.
Undersea Sinkholes
In 2016 scientists are reported to have measured the world’s deepest sinkhole in the South China Sea, toppling Dean’s Blue Hole in the Bahamas, previously thought to be the deepest sea sinkhole in the world.
The sinkhole in the South China Sea has been named the Dragon Hole and is 987 feet or 300 meters deep, located at a coral reef nearby the Paracel islands. A blue hole is an undersea sink hole that is visible from the surface due to the difference in the hues of the waters.
Such sinkholes are likely to provide undersea passages to cave systems and are usually steep-walled depressions. Due to the poor water circulation they are usually anoxic, meaning that oxygen percolation is very poor and diminishes after a certain depth, lending them averse to most life at great depths other than bacteria.
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The United Nations has shaped so much of global co-operation and regulation that we wouldn’t recognise our world today without the UN’s pervasive role in it. So many small details of our lives – such as postage and copyright laws – are subject to international co-operation nurtured by the UN.
In its 75th year, however, the UN is in a difficult moment as the world faces climate crisis, a global pandemic, great power competition, trade wars, economic depression and a wider breakdown in international co-operation.
Still, the UN has faced tough times before – over many decades during the Cold War, the Security Council was crippled by deep tensions between the US and the Soviet Union. The UN is not as sidelined or divided today as it was then. However, as the relationship between China and the US sours, the achievements of global co-operation are being eroded.
The way in which people speak about the UN often implies a level of coherence and bureaucratic independence that the UN rarely possesses. A failure of the UN is normally better understood as a failure of international co-operation.
We see this recently in the UN’s inability to deal with crises from the ethnic cleansing of the Rohingya Muslims in Myanmar, to civil conflict in Syria, and the failure of the Security Council to adopt a COVID-19 resolution calling for ceasefires in conflict zones and a co-operative international response to the pandemic.
The UN administration is not primarily to blame for these failures; rather, the problem is the great powers – in the case of COVID-19, China and the US – refusing to co-operate.
Where states fail to agree, the UN is powerless to act.
Marking the 75th anniversary of the official formation of the UN, when 50 founding nations signed the UN Charter on June 26, 1945, we look at some of its key triumphs and resounding failures.
Five successes
1. Peacekeeping
The United Nations was created with the goal of being a collective security organisation. The UN Charter establishes that the use of force is only lawful either in self-defence or if authorised by the UN Security Council. The Security Council’s five permanent members, being China, US, UK, Russia and France, can veto any such resolution.
The UN’s consistent role in seeking to manage conflict is one of its greatest successes.
A key component of this role is peacekeeping. The UN under its second secretary-general, the Swedish statesman Dag Hammarskjöld – who was posthumously awarded the Nobel Peace prize after he died in a suspicious plane crash – created the concept of peacekeeping. Hammarskjöld was responding to the 1956 Suez Crisis, in which the US opposed the invasion of Egypt by its allies Israel, France and the UK.
UN peacekeeping missions involve the use of impartial and armed UN forces, drawn from member states, to stabilise fragile situations. “The essence of peacekeeping is the use of soldiers as a catalyst for peace rather than as the instruments of war,” said then UN Secretary-General Javier Pérez de Cuéllar, when the forces won the 1988 Nobel Peace Prize following missions in conflict zones in the Middle East, Africa, Asia, Central America and Europe.
However, peacekeeping also counts among the UN’s major failures.
2. Law of the Sea
Negotiated between 1973 and 1982, the UN Convention on the Law of the Sea (UNCLOS) set up the current international law of the seas. It defines states’ rights and creates concepts such as exclusive economic zones, as well as procedures for the settling of disputes, new arrangements for governing deep sea bed mining, and importantly, new provisions for the protection of marine resources and ocean conservation.
Mostly, countries have abided by the convention. There are various disputes that China has over the East and South China Seas which present a conflict between power and law, in that although UNCLOS creates mechanisms for resolving disputes, a powerful state isn’t necessarily going to submit to those mechanisms.
Secondly, on the conservation front, although UNCLOS is a huge step forward, it has failed to adequately protect oceans that are outside any state’s control. Ocean ecosystems have been dramatically transformed through overfishing. This is an ecological catastrophe that UNCLOS has slowed, but failed to address comprehensively.
3. Decolonisation
The idea of racial equality and of a people’s right to self-determination was discussed in the wake of World War I and rejected. After World War II, however, those principles were endorsed within the UN system, and the Trusteeship Council, which monitored the process of decolonisation, was one of the initial bodies of the UN.
Although many national independence movements only won liberation through bloody conflicts, the UN has overseen a process of decolonisation that has transformed international politics. In 1945, around one third of the world’s population lived under colonial rule. Today, there are less than 2 million people living in colonies.
When it comes to the world’s First Nations, however, the UN generally has done little to address their concerns, aside from the non-binding UN Declaration on the Rights of Indigenous Peoples of 2007.
4. Human rights
The Human Rights Declaration of 1948 for the first time set out fundamental human rights to be universally protected, recognising that the “inherent dignity and of the equal and inalienable rights of all members of the human family is the foundation of freedom, justice and peace in the world”.
Since 1948, 10 human rights treaties have been adopted – including conventions on the rights of children and migrant workers, and against torture and discrimination based on gender and race – each monitored by its own committee of independent experts.
The language of human rights has created a new framework for thinking about the relationship between the individual, the state and the international system. Although some people would prefer that political movements focus on ‘liberation’ rather than ‘rights’, the idea of human rights has made the individual person a focus of national and international attention.
5. Free trade
Depending on your politics, you might view the World Trade Organisation as a huge success, or a huge failure.
The WTO creates a near-binding system of international trade law with a clear and efficient dispute resolution process.
The majority Australian consensus is that the WTO is a success because it has been good for Australian famers especially, through its winding back of subsidies and tariffs.
However, the WTO enabled an era of globalisation which is now politically controversial.
Recently, the US has sought to disrupt the system. In addition to the trade war with China, the Trump Administration has also refused to appoint tribunal members to the WTO’s Appellate Body, so it has crippled the dispute resolution process. Of course, the Trump Administration is not the first to take issue with China’s trade strategies, which include subsidises for ‘State Owned Enterprises’ and demands that foreign firms transfer intellectual property in exchange for market access.
The existence of the UN has created a forum where nations can discuss new problems, and climate change is one of them. The Intergovernmental Panel on Climate Change (IPCC) was set up in 1988 to assess climate science and provide policymakers with assessments and options. In 1992, the UN Framework Convention on Climate Change created a permanent forum for negotiations.
However, despite an international scientific body in the IPCC, and 165 signatory nations to the climate treaty, global greenhouse gas emissions have continued to increase.
Under the Paris Agreement, even if every country meets its greenhouse gas emission targets we are still on track for ‘dangerous warming’. Yet, no major country is even on track to meet its targets; while emissions will probably decline this year as a result of COVID-19, atmospheric concentrations of greenhouse gases will still increase.
This illustrates a core conundrum of the UN in that it opens the possibility of global cooperation, but is unable to constrain states from pursuing their narrowly conceived self-interests. Deep co-operation remains challenging.
Five failures of the UN
1. Peacekeeping
During the Bosnian War, Dutch peacekeeping forces stationed in the town of Srebrenica, declared a ‘safe area’ by the UN in 1993, failed in 1995 to stop the massacre of more than 8000 Muslim men and boys by Bosnian Serb forces. This is one of the most widely discussed examples of the failures of international peacekeeping operations.
On the massacre’s 10th anniversary, then UN Secretary General Kofi Annan wrote that the UN had “made serious errors of judgement, rooted in a philosophy of impartiality”, contributing to a mass murder that would “haunt our history forever”.
If you look at some of the other infamous failures of peacekeeping missions – in places such as Rwanda, Somalia and Angola – it is the limited powers given to peacekeeping operations that have resulted in those failures.
2. The invasion of Iraq
The invasion of Iraq by the US in 2003, which was unlawful and without Security Council authorisation, reflects the fact that the UN is has very limited capacity to constrain the actions of great powers.
The Security Council designers created the veto power so that any of the five permanent members could reject a Council resolution, so in that way it is programmed to fail when a great power really wants to do something that the international community generally condemns.
In the case of the Iraq invasion, the US didn’t veto a resolution, but rather sought authorisation that it did not get. The UN, if you go by the idea of collective security, should have responded by defending Iraq against this unlawful use of force.
The invasion proved a humanitarian disaster with the loss of more than 400,000 lives, and many believe that it led to the emergence of the terrorist Islamic State.
3. Refugee crises
The UN brokered the 1951 Refugee Convention to address the plight of people displaced in Europe due to World War II; years later, the 1967 Protocol removed time and geographical restrictions so that the Convention can now apply universally (although many countries in Asia have refused to sign it, owing in part to its Eurocentric origins).
Despite these treaties, and the work of the UN High Commission for Refugees, there is somewhere between 30 and 40 million refugees, many of them, such as many Palestinians, living for decades outside their homelands. This is in addition to more than 40 million people displaced within their own countries.
While for a long time refugee numbers were reducing, in recent years, particularly driven by the Syrian conflict, there have been increases in the number of people being displaced.
During the COVID-19 crisis, boatloads of Rohingya refugees were turned away by port after port. This tragedy has echoes of pre-World War II when ships of Jewish refugees fleeing Nazi Germany were refused entry by multiple countries.
And as a catastrophe of a different kind looms, there is no international framework in place for responding to people who will be displaced by rising seas and other effects of climate change.
4. Conflicts without end
Across the world, there is a shopping list of unresolved civil conflicts and disputed territories.
Palestine and Kashmir are two of the longest-running failures of the UN to resolve disputed lands. More recent, ongoing conflicts include the civil wars in Syria and Yemen.
The common denominator of unresolved conflicts is either division among the great powers, or a lack of international interest due to the geopolitical stakes not being sufficiently high. For instance, the inaction during the Rwandan civil war in the 1990s was not due to a division among great powers, but rather a lack of political will to engage.
In Syria, by contrast, Russia and the US have opposing interests and back opposing sides: Russia backs the government of the Syrian dictator Bashar al-Assad, whereas the US does not.
5. Acting like it’s 1945
The UN is increasingly out of step with the reality of geopolitics today.
The permanent members of the Security Council reflect the division of power internationally at the end of World War II. The continuing exclusion of Germany, Japan, and rising powers such as India and Indonesia, reflects the failure to reflect the changing balance of power.
Also, bodies such as the IMF and the World Bank, which are part of the UN system, continue to be dominated by the West. In response, China has created potential rival institutions such as the Asian Infrastructure Investment Bank.
Western domination of UN institutions undermines their credibility. However, a more fundamental problem is that institutions designed in 1945 are a poor fit with the systemic global challenges – of which climate change is foremost – that we face today.