New York – The world’s leading climate science organisations issued a landmark report on Sunday, warning that the planet is witnessing a critical moment due to climate change and the increase of the average global temperature in the past five years.
According to the report, named “United in Science”, the period from 2015 to 2019 is on track to be the warmest of any equivalent period on record. It is currently estimated to be 1.1C above pre-industrial (1850–1900) times.
The report which coincides with the United Nations (UN) Climate Action Summit, highlighted the major socio-economic and environmental impacts of this increase in heat.
Warming could occur through the widespread and long-lasting heatwaves, record-breaking fires, and other devastating events, such as tropical cyclones, floods, and drought.
According to the United Nations Environment Programme’s (UNEP) Emissions Gap Report 2019, the global greenhouse gas emissions are not estimated to peak by 2030, let alone by 2020, if current climate policies and ambition levels of the Nationally Determined Contributions (NDCs) are maintained. The NDCs are the UN’s intended reductions in greenhouse gas emissions.
Preliminary findings from the report indicate that greenhouse gas emissions continued to rise in 2018.
The current NDCs are estimated to lower global emissions in 2030 by up to 6 GtCO2e, if current policies are followed. This ambition needs to be roughly tripled to align with the 2C limit and must increase to around fivefold to align with the 1.5C limit.
United in Science
The United in Science report includes details on the state of the climate and presents trends in the emissions and atmospheric concentrations of the main greenhouse gases.
It highlights the urgency of fundamental socio-economic transformation in key sectors, such as land use and energy, in order to avert dangerous global temperature increase with potentially irreversible impacts. It also examines tools to support both mitigation and adaptation.
The Science Advisory Group to the UN Climate Action Summit is co-chaired by the World Meteorological Organization (WMO) Secretary-General Petteri Taalas and Leena Srivastava, former vice chancellor of TERI School of Advanced Studies.
The Science Advisory Group announced, “The report provides a unified assessment of the state of our Earth system under the increasing influence of anthropogenic climate change, of humanity’s response thus far, and of the far-reaching changes that science projects for our global climate in the future.”
According to the group, the scientific data and findings presented in the report represent the latest authoritative information on these topics. It also highlights the urgent need for the development of concrete actions that halt the worst effects of climate change.
Greenhouse Gas Concentrations
Findings of the report urge the world to take action since the levels of the main long-lived greenhouse gases, such as carbon dioxide, methane, and nitrous oxide, reached new highs.
In 2018, global CO2 concentration was 407.8 parts per million (ppm), 2.2 ppm higher than 2017. Preliminary data from a subset of greenhouse gas monitoring sites for 2019 indicate that CO2 concentrations are on track to reach or even exceed 410 ppm by the end of 2019.
Additionally, the growth rate of CO2 averaged over three consecutive decades increased from 1.42 ppm/year, to 1.86 ppm/year, and to 2.06 ppm/year.
The last time Earth’s atmosphere contained 400 ppm CO2 was about three to five million years ago. At that time, global surface temperatures were 2-3C warmer than today, ice sheets in Greenland and West Antarctica melted, parts of East Antarctica ice retreated, all causing global sea level rise of 10-20m.
Carbon Budget
Carbon dioxide emissions grew 2% and reached a record high of 37bn tonnes in 2018. There is still no sign of a peak in global emissions, even though they are growing slower than the global economy.
The report pointed out that the current economic and energy trends suggest that emissions will be at least as high in 2019 as in 2018. It also expects that the global GDP will grow at 3.2% in 2019, and if the global economy decarbonised at the same rate as in the last 10 years, it would still lead to an increase in global emissions.
Regarding the notable increase in renewable fuels over the past decade, the report says that the global energy system is still dominated by fossil fuel sources.
Despite this extraordinary increase in renewable fuels use worldwide, it is not sufficient since the annual increase in global energy use is greater. This could give the fossil fuel use greater chances to grow, which the report calls to be halted immediately.
The report renews the calls that net-zero emissions needed to stabilise the climate require both an acceleration in use of non-carbon energy sources and a rapid decline in the global share of fossil fuels in the energy mix.
It further stresses the necessity of reducing deforestation and expanding natural CO2 sinks, such as vegetation and oceans, particularly those in forests and soils that can be improved by better management and habitat restoration.
Natural CO2 sinks remove about half of all emissions from human activities. Unfortunately, if the level of increase in CO2 emissions continued in the same level, these natural sinks will not be able to contain the emissions from human activities.
In 2018, the UN Intergovernmental Panel on Climate Change (IPCC) urged the international community in a report, to take rapid steps to counter climate change and its expected impacts.
The report stated that by 2006–2015, human activity warmed the world by 0.87C compared to pre-industrial times. It also urged that if the current warming rate continues, the world would reach human–induced global warming of 1.5C around 2040.
The report which took three years to be prepared, addressed the impacts of global warming of 1.5C above pre-industrial levels and related global greenhouse gas emission pathways.
According to the report, the way to limit global warming to 1.5C is projected to involve the annual average investment needs in the energy system of around $2.4trn between 2016 and 2035, representing about 2.5% of the world’s GDP.
Water is coming
During the period from 1979 to 2018, the arctic summer sea-ice extent has declined at a rate of approximately 12% per decade. The four lowest values of winter sea-ice extent occurred between 2015 and 2019.
The United in Science report noted that the amount of ice lost annually from the Antarctic ice sheet increased at least six-fold between 1979 and 2017. Glacier mass loss for 2015-2019 is the highest for any five-year period on record.
“The observed rate of global mean sea-level rise accelerated from 3.04mm per year during the period 1997-2006 to approximately 4mm per year during the period 2007-2016,” the report states.
The report refers this increase to the increased rate of ocean warming and melting of the Greenland and West Antarctica ice sheets. There has been an overall increase of 26% in ocean acidity since the beginning of the industrial era.
Egypt is a typical example of a developing country which is highly vulnerable to the phenomenon, facing numerous threats to its economic, social, and environmental sustainability, according to a study by the World Resources Institute.
This puts Egypt under the pressure of taking its measures to combat climate change and take part in the international efforts to limit temperature rise by 2100 to less than 1.5C in accordance with the Paris Agreement.
