The Tanzanian delegation to the IPCC 42 session held this week, Tanzania Meteorological Agency (TMA) director general Agnes Kijazi (centre), TMA director of research and applied meteorology Ladislaus Chang’a (left) and the agency’s international affairs manager Wilbert Timiza. PHOTO | FILE
What you need to know:
Experts warn that rising temperatures have a very detrimental impact on the environment; underscore that climate change threaten development and impact economic growth
New York. Speaking on Thursday at a United Nations forum to invigorate political momentum on climate change, the head of a major UN panel on climate change underlined that human influence on the climate system cannot be disputed.
“[Research has] demonstrated the link between cumulative past, present and future carbon dioxide (CO2) emissions and a given temperature rise,” Hoesung Lee, the chair of the Intergovernmental Panel on Climate Change (IPCC), stressed in his keynote address at the UN General Assembly High-Level action event on Thursday. “Bigger emissions now mean higher temperature in the future,” he added.
In his address, Mr Lee drew examples from the Fifth Assessment Report (AR5) issued by the IPCC in 2014 and said that since then, warming has continued and global mean temperature rise has reached more than one degree Celsius above pre-industrial levels in 2015 and 2016.
Such observed warming led at the centre of the climate model projections assessed in the Report, he explained. Underscoring that climate change threatened development, impacted economic growth, made poverty eradication efforts all the more difficult and severely underlined food security, Mr. Lee said that rising temperatures also had a very detrimental impact on the environment.
“Oceans are continuing to warm, acidify and lose oxygen,” he said, “Warm water coral reefs are already under pressure and 90 per cent would suffer significant risk from global warming of 1.5 degree Celsius.” Touching upon the Sixth Assessment Report (AR6), which will be completed with a synthesis report in 2022, said Mr Lee that it will be ready in good time for the first global stocktaking under the Paris Agreement on climate change the following year.
Fighting poverty and hunger
He also said scientific research had illustrated that efforts to address climate change and pursuit of sustainable development could support each other, citing the following example: “If food waste was a country, it would be the world’s third biggest emitter of greenhouse gases [therefore] reducing food waste globally can help fight poverty and hunger while stabilising the climate.”
He also said that in its subsequent reports, the IPCC sought to improve its scientific understanding of the economics of addressing climate change, such as of the benefits on health from clean air or the impact on energy security, balance of payments and jobs from energy efficiency.
In his remarks he further mentioned that researchers were on working on new methods to better observe and understand the climate. These will be crucial to help improve weather forecasts and climate projections.
“This science underpins the IPCC’s policy-relevant assessments and is essential for sustainable development planning,” he noted, calling for continued support the vital research.
Concluding his address, Mr Lee highlighted that the expression “business as usual” was often seen for not taking action on climate. “Business will be very far from usual in a world of no mitigation, which could see temperatures rise by an average 40 or more over the century,” he said stressing that economic development could not be pursued by relying on high-carbon technology.
Actions to limit climate change
“Actions to limit climate change have a positive impact on the domestic economy and help improve human well-being, and adaptation reduces vulnerability, supporting inclusive and equitable development.”
The Intergovernmental Panel on Climate Change (IPCC) is an international body for assessing the science related to climate change. It was up in 1988 by the World Meteorological Organisation (WMO) and UN Environment Programme (UNEP) to provide policymakers with regular assessments of the scientific basis of climate change, its impacts and future risks, and options for adaptation and mitigation.
In another development, in a world where the demand for water continues growing and the resource is finite, a new United Nations report argues that wastewater, discarded into the environment every day, once treated, can help meet the needs for freshwater and for raw materials for energy and agriculture.
Needless to mention, treating wastewater and removing pollutants can also remarkably reduce the impact on the environment as well as on health.
“Improved wastewater management is as much about reducing pollution at the source, as removing contaminants from wastewater flows, reusing reclaimed water and recovering useful by-products [as it is about increasing] social acceptance of the use of wastewater,” noted Irina Bokova, the Director-General of the UN Educational, Scientific and Cultural Organisation (Unesco) director-general in her foreword to the World Water Development Report 2017 – Wastewater: An untapped resource.
Improved management of wastewater
The report, launched in Durban, South Africa on Wednesday, on the occasion of World Water Day, also highlights that improved management of wastewater is essential in achieving the 2030 Agenda for Sustainable Development.
“It’s all about carefully managing and recycling the water that runs through our homes, factories, farms and cities,” said Guy Ryder, the director-general of the UN International Labour Organisation (ILO) and the Chair of UN-Water, urging for reducing and safely reusing more wastewater.
“Everyone can do their bit to achieve the Sustainable Development Goal target to halve the proportion of untreated wastewater and increase safe water reuse by 2030.”
Sustainable Development Goal 6 (SDG6) has specific targets on halving the proportion of untreated wastewater and substantially increasing recycling and safe reuse globally (target 6.3) as well as supporting countries in wastewater treatment, recycling and reuse technologies (target 6.a).
Release of waste water into the environment
The report also reveals that low-income countries are particularly impacted by the release of waste water into the environment without being either treated or collected, where, on average, only 8 per cent of domestic and industrial wastewater is treated, compared to 70 per cent in high-income countries.
As a result, in many regions of the world, water contaminated by bacteria, nitrates, phosphates and solvents is discharged into rivers and lakes ending up in the oceans, with negative consequences for the environment and public health.
Pollution from pathogens
For instance, in Latin America, Asia and Africa, pollution from pathogens from human and animal excreta affects almost one third of rivers, endangering the lives of millions of people.
Furthermore, growing awareness on the presence of hormones, antibiotics, steroids and endocrine disruptors in wastewater poses a new set of complexities as their impact on the environment and health have yet to be fully understood.
These set of challenges underscore the need for urgent action on collection, treatment and safe use of wastewater.
In addition to providing a safe alternative source for freshwater, wastewater is also a potential source of raw materials, noted the report.
Treatment of human urine and excrement
Owing to developments in treatment techniques, certain nutrients, like phosphorus and nitrates, can now be recovered from sewage and sludge and turned into fertiliser. It is estimated that nearly 22 per cent of the global demand for phosphorus (a depleting mineral resource) can be met by treating human urine and excrement.
Similarly, organic substances contained in wastewater can be used to produce biogas, which could power wastewater treatment facilities as well as contribute to energy needs of local communities. In addition, use of treated wastewater is growing for agricultural irrigation. At least 50 countries around the globe are now using treated wastewater for this purpose, accounting for an estimated 10 per cent of all irrigated land.
Augmenting drinking water supplies
Lastly, the report also mentions that treated wastewater can augment drinking water supplies, although this is still a marginal practice. Cities such as Singapore, San Diego (United States), and Windhoek (Namibia) have been treating wastewater to supplement drinking water reserves.
A great example is use of treated wastewater, long practised by astronauts, such as those on the International Space Station, who have been reusing the same recycled water for over 16 years. (UN News Centre)
