volcanoes helped offset manmade warming
Last Updated : GMT 06:49:16
Arab Today, arab today
Arab Today, arab today
Last Updated : GMT 06:49:16
Arab Today, arab today

While temperatures have risen relentlessly

Volcanoes helped offset man-made warming

Arab Today, arab today

Arab Today, arab today Volcanoes helped offset man-made warming

Smoke and ash rise from Mount Kelud
Paris - Arab Today

Smoke and ash rise from Mount Kelud Paris - Arab Today Volcanoes spewing Sun-reflecting particles into the atmosphere have partly offset the effects of Man's carbon emissions over a 15-year period that has become a global-warming battleground, researchers said Sunday. A so-called hiatus in warming since 1998 has pitched climate sceptics against mainstream scientists. While temperatures have risen relentlessly -- 13 of the 14 warmest years on record occurred since the start of the century -- they tracked far below the increase in man-made greenhouse gases. This gap between the expected and actual temperatures has been cited by sceptics as proof that human-induced global warming is either a green scare or bad science. But a study in the journal Nature Geoscience said volcanic eruptions helped explain the apparent warming slowdown. Researchers using satellite data found a link between surface temperatures and the impact from nearly 20 volcanic eruptions since 2000. Sulphuric droplets disgorged by the volcanoes reflected sunlight and slightly cool the lower atmosphere, they said. The effect of these "aerosols" accounted for as much as 15 percent of the gap between expected and measured temperatures between 1998 and 2012, according to the team's figures. "The 'warming hiatus' since 1998 has a number of different causes," study co-author Ben Santer of the Lawrence Livermore National Laboratory in California told AFP by email. "The cooling caused by early 21st century volcanic eruptions is one of the causes." Other explanations for the "hiatus" have been a bigger-than-expected takeup of atmospheric heat by the ocean, or a decline in solar activity. Blockbuster eruptions, notably that of Mount Pinatubo in the Philippines in 1991, were known to have discernible cooling effects on Earth's surface. But volcanoes have not featured in the "hiatus" debate mainly because there had been no major eruptions since the mooted pause began in 1998, only smaller ones whose impact is harder to measure. - Better models needed - This is a gap, as it left computer models of climate change incomplete, the new study suggested. "Better observations of eruption-specific properties of volcanic aerosols are needed, as well as improved representation of these... in climate model simulations," it said. Global warming sceptics have pointed to the "hiatus" as proof of flaws in models used to predict warming and thus play a key role in driving policies to tackle climate change. They contend that these models exaggerate the heat-trapping effect from carbon dioxide (CO2) emitted by fossil fuel burning. Santer said the new findings "do not support" such an argument. "We've been lucky that a natural cooling influence (an uptick in 21st century volcanic activity) has partly counteracted human-caused warming," he said. "We do not know how volcanic activity will evolve over the coming decades, and thus we do not know how long our luck will continue." Experts generally agree that Earth is on track for greatly exceeding the maximum two degrees Celsius (3.6 degrees Fahrenheit) of warming targeted in UN climate negotiations. Last year the level of carbon dioxide (CO2) in the atmosphere crossed a threshold of 400 parts per million (ppm) -- a level never experienced by humans. CO2 concentrations are rising at two or three ppm per year, driven especially by the burning of coal in emerging economies. Commenting on the study, Piers Forster, a professor of climate change at the University of Leeds, said it confirmed that volcanoes contributed to the slowdown, but could not be the only cause. "Volcanoes give us only a temporary respite from the relentless warming pressure of continued increases in CO2," he added. Source: AFP

arabstoday
arabstoday

Name *

E-mail *

Comment Title*

Comment *

: Characters Left

Mandatory *

Terms of use

Publishing Terms: Not to offend the author, or to persons or sanctities or attacking religions or divine self. And stay away from sectarian and racial incitement and insults.

I agree with the Terms of Use

Security Code*

volcanoes helped offset manmade warming volcanoes helped offset manmade warming

 



Name *

E-mail *

Comment Title*

Comment *

: Characters Left

Mandatory *

Terms of use

Publishing Terms: Not to offend the author, or to persons or sanctities or attacking religions or divine self. And stay away from sectarian and racial incitement and insults.

I agree with the Terms of Use

Security Code*

volcanoes helped offset manmade warming volcanoes helped offset manmade warming

 



GMT 14:58 2017 Tuesday ,28 February

Humans spark most US wildfires

GMT 00:49 2017 Tuesday ,28 February

New vehicle scanner to ease Oman border rush

GMT 10:50 2018 Monday ,08 January

L'anza unveils sprayable styling paste Airpaste

GMT 16:40 2012 Monday ,20 February

New Ferrari Enzo

GMT 13:47 2013 Friday ,22 March

FM: Greece takeover process of Cypriot banks

GMT 19:13 2017 Monday ,16 October

6 wounded in USA oil rig blaze near New Orleans

GMT 16:34 2016 Sunday ,25 September

Pakistani air force jet crashes, killing pilot

GMT 20:53 2017 Wednesday ,14 June

Media council abandon complaint against writer

GMT 20:59 2017 Tuesday ,31 October

IMF official says Egypt's economy

GMT 15:19 2017 Wednesday ,29 November

Five things to watch out for in 2018
Arab Today, arab today
 
 Arab Today Facebook,arab today facebook  Arab Today Twitter,arab today twitter Arab Today Rss,arab today rss  Arab Today Youtube,arab today youtube  Arab Today Youtube,arab today youtube

Maintained and developed by Arabs Today Group SAL.
All rights reserved to Arab Today Media Group 2025 ©

Maintained and developed by Arabs Today Group SAL.
All rights reserved to Arab Today Media Group 2025 ©

arabstoday arabstoday arabstoday arabstoday
arabstoday arabstoday arabstoday
arabstoday
بناية النخيل - رأس النبع _ خلف السفارة الفرنسية _بيروت - لبنان
arabstoday, Arabstoday, Arabstoday