Global Warming Current Affairs

IPCC Special Report on Climate Change: Key Points

United Nations Intergovernmental Panel on Climate Change (IPCC) has released special report on global warming in Incheon, South Korea. The report includes contributions from 91 authors and review editors from 40 countries. It will be key scientific input in upcoming Katowice Climate Change Conference in Poland in December 2018.

Key Points from report

It clearly shows how half degree of warming makes big difference, adversely impacting global population and overall ecosystem through intense heat waves, melting of Arctic, sea level rise, erratic rainfall, reduction of farm yield and vanishing of living species.

It is possible to meet new warming target, provided nations together take rapid and far reaching transitions over next 10 to 20 years in energy, industry, land use, buildings, transport and cities to cut emissions and reach net zero around 2050 — 25 years earlier than planned under earlier 2-degree goal.

It lists four pathways to curb global warming and through which the 1.5 degree target can be achieved. In each of pathways, global average temperature is projected to overshoot 1.5 degrees Celsius target by some amount before returning to that level before the end of this century.

Each of these pathways is also dependent on some amount of Carbon Dioxide Removal (CDR), a reference to physical removal of stock of CO2 from atmosphere to reduce its concentrations. Varying amounts between 100 to 1000 gigatons (billion tonnes) of CO2 needs to be removed from atmosphere in these four pathways.

It refers to climate models that project robust differences in regional climate characteristics between present-day and global warming of 1.5 degrees Celsiusand between 1.5 and 2 degrees Celsius. These differences include increase in mean temperatures in both land ocean regions, hot extremes in most inhabited regions, heavy precipitation in several regions and probability of drought and precipitation deficits in some regions.

Advantages of keeping global temperature rise within 1.5 degrees celsius

It also lists several specific advantages of keeping the global temperature rise within 1.5 degrees celsius from pre-industrial levels. By 2100, global sea level rise would be 10 cm lower with global warming of 1.5 degrees compared with 2 degrees Celsius. Arctic Ocean free of sea ice in summer would be once per century with global warming of 1.5 degrees, compared with at least once per decade with 2 degrees Celsius. Coral reefs will decline by 70-90% with global warming of 1.5 degrees, whereas virtually all (over 99%) would be lost with 2 degrees Celsius. It also points out that climate-related risks to health, livelihoods, food security, water supply, human security and economic growth are projected to increase with global warming of 1.5 degrees Celsius and increase further with 2 degrees Celsius.

Intergovernmental Panel on Climate Change (IPCC)

IPCC is the leading international body for the assessment of climate change. It was established in 1988 by the United Nations Environment Programme (UNEP) and World Meteorological Organization (WMO). It is headquartered in Geneva, Switzerland.

Currently 195 countries are its members. It comprises a group of several hundred scientists of different nationality who assess climate change science. Every 5 or 6 years, IPCC comes out with comprehensive periodic reports on Climate Change called Assessment Reports (AR).

Functions: IPCC neither monitors climate related parameters or data nor does it conduct any research work. It merely assesses the most recent scientific, socio-economic and technical information produced worldwide relevant to the understanding of climate change.

Awards: IPCC’s 4th AR had helped them to win Nobel Peace Prize in 2007. During this time R.K. Pachauri was its Chairman.

Month: Categories: Environment Current Affairs 2018

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Earth at risk of becoming irreversible hothouse: Study

According to recent study, earth is at the risk of entering an irreversible hothouse condition – where the global temperatures will rise by four to five degrees even if targets under 2015 Paris climate deal are met. Hothouse Earth climate will in long-term stabilise at global average of 4-5 degrees Celsius higher than pre-industrial temperatures with sea level 10-60 metres higher than today.

Key Highlights of Study

Currently, global average temperatures are just over 1 degree Celsius above pre-industrial and rising at 0.17 degree Celsius per decade. Keeping global warming to within 1.5-2 degrees Celsius as agreed in 2015 Paris climate agreement by around 200 countries may be more difficult than previously assessed.

Human-induced global warming of two degrees Celsius may trigger other Earth system processes often called feedbacks that can drive further warming even if greenhouse gases emissions are stopped. Avoiding this scenario will require redirection of human actions from exploitation to stewardship of Earth system.

The study consider ten natural feedback processes, some of which are tipping elements that lead to abrupt change if critical threshold is crossed. These feedbacks can turn from being friend that stores carbon to foe that emits it uncontrollably in warmer world.

These feedbacks include permafrost thaw, weakening land and ocean carbon sinks, loss of methane hydrates from ocean floor, increasing bacterial respiration in oceans, boreal forest dieback, Amazon rainforest dieback, reduction of northern hemisphere snow cover, loss of Arctic summer sea ice and reduction of Antarctic sea ice and polar ice sheets. These feedbacks tipping elements can potentially act like row of dominoes. Once one is pushed over, it pushes Earth towards another.

Month: Categories: Environment Current Affairs 2018

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