IPCC Report Part III: Future Global Climate Change

http://www.accuweather.com/en/weather-blogs/climatechange/ipcc-report-part-iii-future-gl/18400212

This is part III of our coverage of the IPCC's latest assessment report on climate change, which was released Friday.
Today we will highlight the latest projections directly from the IPCC report in regards to future climate change......
--Continued emissions of greenhouse gases will cause further warming and changes in all components of the climate system. Limiting climate change will require substantial and sustained reductions of greenhouse gas emissions.

-- The global mean surface temperature change for the period 2016-2035 relative to 1986-2005 will likely be in the range of 0.3°C to 0.7°C (0.5 F to 1.25 F) (medium confidence). This assessment is based on multiple lines of evidence and assumes there will be no major volcanic eruptions or secular changes in total solar irradiance.


CMIP5 multi-model simulated time series from 1950 to 2100 for change in global annual mean surface temperature relative to 1986-2005. FYI, The RCP2.6 scenario is based on aggressive emissions reduction, while the RCP8.5 is the "business as usual" scenario.

--It is virtually certain that there will be more frequent hot and fewer cold temperature extremes over most land areas on daily and seasonal timescales as global mean temperatures increase. It is very likely that heat waves will occur with a higher frequency and duration. Occasional cold winter extremes will continue to occur.

--Extreme precipitation events over most of the mid-latitude land masses and over wet tropical regions will very likely become more intense and more frequent by the end of this century.
-- Globally, it is likely that the area encompassed by monsoon systems will increase over the 21st century. While monsoon winds are likely to weaken, monsoon precipitation is likely to intensify due to the increase in atmospheric moisture. Monsoon onset dates are likely to become earlier or not to change much. Monsoon retreat dates will likely be delayed, resulting in lengthening of the monsoon seas on in many regions.
--The global ocean will continue to warm during the 21st century. Heat will penetrate from the
surface to the deep ocean and affect ocean circulation.


--Based on an assessment of the subset of models (see IPCC image below) that most closely reproduce the climatological mean state and 1979-2012 trend of the Arctic sea ice extent, a nearly ice-free Arctic Ocean in September before mid-century is likely for RCP8.5 (medium confidence). A projection of when the Arctic might become nearly ice-free in September in the 21st century cannot be made with confidence for the other scenarios.
CMIP5 multi-model simulated time series from 1950 to 2100 for Northern Hemisphere September sea ice extent (5 year running mean). Image courtesy of the IPCC.

-- In the Antarctic, a decrease in sea ice extent and volume is projected with low confidence
for the end of the 21st century as global mean surface temperature rises.
--Global mean sea level will continue to rise during the 21st century (see below). Under all RCP scenarios the rate of sea level rise will very likely exceed that observed during 1971-2010 due to increased ocean warming and increased loss of mass from glaciers and ice sheets.
Projected global sea level rise (meters) through 2100 based on different scenarios. Image courtesy of the IPCC.

The views expressed are those of the author and not necessarily those of AccuWeather, Inc. or AccuWeather.com