There is no doubt, therefore, that the subject of adaptation in a «4 °C world» (here, we use this shorthand to refer to the world with a serious prospect of
average global warming of 4 °C or more) will become an increasingly urgent concern.
It's hard to deny that there may be some risk, just as its impossible to deny one might get hit by a car tomorrow morning, but this is speculative in the extreme, and ignores a vast number of counteracting «negative» feedbacks from the biosphere, as well as the lack of
average global warming of the last 18 years.
Not exact matches
The LCA examined the effects
of a 1 kilogram industry -
average corrugated product manufactured in 2014 on seven environmental impact indicators:
global warming potential (greenhouse gas emissions), eutrophication, acidification, smog, ozone depletion, respiratory effects, fossil fuel depletion; and four inventory indicators: water use, water consumption, renewable energy demand, and non-renewable energy demand.
Most scientists and climatologists agree that weird weather is at least in part the result
of global warming — a steady increase in the
average temperature
of the surface
of the Earth thought to be caused by increased concentrations
of greenhouse gasses produced by human activity.
The report found that while disposable nappies used over 2 1/2 years would have a
global warming impact
of 550 kg
of CO2 reusable nappies produced 570 kg
of CO2 on
average.
During the Eocene, the concentration
of carbon dioxide in the atmosphere was more than 560 parts per million, at least twice preindustrial levels, and the epoch kicked off with a
global average temperature more than 8 degrees Celsius — about 14 degrees Fahrenheit —
warmer than today, gradually cooling over the next 22 million years.
One aerosol, black carbon, is
of increasing concern for Arctic nations worried about the pace
of climate change in the far north, which is
warming twice as fast as the
global average.
With Arctic temperatures
warming twice as fast as the
global average, scientists estimate thawing permafrost could release large amounts
of carbon into the atmosphere through the end
of the century with significant climate impacts.
But they've been especially interested in the most recent period
of abrupt
global warming, the Bølling - Allerød, which occurred about 14,500 years ago when
average temperatures in Greenland rose about 15 degrees Celsius in about 3,000 years.
Combining the asylum - application data with projections
of future
warming, the researchers found that an increase
of average global temperatures
of 1.8 °C — an optimistic scenario in which carbon emissions flatten globally in the next few decades and then decline — would increase applications by 28 percent by 2100, translating into 98,000 extra applications to the EU each year.
The
average global temperature change for the first three months
of 2016 was 1.48 °C, essentially equaling the 1.5 °C
warming threshold agreed to by COP 21 negotiators in Paris last December.
Three approaches were used to evaluate the outstanding «carbon budget» (the total amount
of CO2 emissions compatible with a given
global average warming) for 1.5 °C: re-assessing the evidence provided by complex Earth System Models, new experiments with an intermediate - complexity model, and evaluating the implications
of current ranges
of uncertainty in climate system properties using a simple model.
The work by Mark Jacobson, director
of Stanford University's Atmosphere / Energy program and a fellow at the university's Woods Institute, argues that cutting emissions
of black carbon may be the fastest method to limit the ongoing loss
of ice in the Arctic, which is
warming twice as fast as the
global average.
The strength and path
of the North Atlantic jet stream and the Greenland blocking phenomena appear to be influenced by increasing temperatures in the Arctic which have
averaged at least twice the
global warming rate over the past two decades, suggesting that those marked changes may be a key factor affecting extreme weather conditions over the UK, although an Arctic connection may not occur each year.
On one hand, areas
of high climatic stability are predicted to
warm less than the
global average.
Changes in the number
of cosmic rays hitting the atmosphere due to changes in solar activity can not explain
global warming, as
average cosmic ray intensities have been increasing since 1985 even as the world has
warmed — the opposite
of what should happen if cosmic rays produce climate - cooling clouds.
«The result is not a surprise, but if you look at the
global climate models that have been used to analyze what the planet looked like 20,000 years ago — the same models used to predict
global warming in the future — they are doing, on
average, a very good job reproducing how cold it was in Antarctica,» said first author Kurt Cuffey, a glaciologist at the University
of California, Berkeley, and professor
of geography and
of earth and planetary sciences.
The results show that even though there has been a slowdown in the
warming of the
global average temperatures on the surface
of Earth, the
warming has continued strongly throughout the troposphere except for a very thin layer at around 14 - 15 km above the surface
of Earth where it has
warmed slightly less.
One period
of particular interest is a
warm, wet interglacial stage known as the Eemian that occurred from 124,000 to 119,000 years ago, featuring
average global temperatures about 2 °C
warmer than today.
Increased flow
of the East Australian Current, for example, has meant waters south - east
of the continent are
warming at two to three times the
global average.
Bowen and colleagues report that carbonate or limestone nodules in Wyoming sediment cores show the
global warming episode 55.5 million to 55.3 million years ago involved the
average annual release
of a minimum
of 0.9 petagrams (1.98 trillion pounds)
of carbon to the atmosphere, and probably much more over shorter periods.
So if you think
of going in [a]
warming direction
of 2 degrees C compared to a cooling direction
of 5 degrees C, one can say that we might be changing the Earth, you know, like 40 percent
of the kind
of change that went on between the Ice Age; and now are going back in time and so a 2 - degree change, which is about 4 degrees F on a
global average, is going to be very significant in terms
of change in the distribution
of vegetation, change in the kind
of climate zones in certain areas, wind patterns can change, so where rainfall happens is going to shift.
Global warming has been going on for so long that most people were not even born the last time the Earth was cooler than
average in 1985 in a shift that is altering perceptions
of a «normal» climate, scientists said.
One
of the planet's hotspots has been the outsized
warming in the Arctic, which is seeing a temperature rise double that
of the
global average.
Warmer than
average temperatures were evident over most
of the
global land surface, except for parts
of western Europe, northern Siberia, parts
of eastern Asia and much
of central Australia stretching north.
Politicians have generally adopted the aim
of limiting
global warming to 2 °C above 19th century
averages, so a 1 °C is not something to be taken lightly.
Statistical analysis
of average global temperatures between 1998 and 2013 shows that the slowdown in
global warming during this period is consistent with natural variations in temperature, according to research by McGill University physics professor Shaun Lovejoy.
In the latter half
of the decade, La Niña conditions persisted in the eastern and central tropical Pacific, keeping
global surface temperatures about 0.1 degree C colder than
average — a small effect compared with long - term
global warming but a substantial one over a decade.
«We examined
average and extreme temperatures because they were always projected to be the measure that is most sensitive to
global warming,» said lead author from the ARC Centre
of Excellence for Climate System Science, Dr Andrew King.
Average composite reflectivity over the CONUS (contiguous US) domain in all 13 years
of the simulations are shown by season (May - June and July - August) and by simulation type (control and psuedo
global warming).
As Pat Michaels, a climatologist and self - described
global warming skeptic at the Cato Institute testified to Congress in July, certain studies
of sensitivity published since 2011 find an
average sensitivity
of 2 degrees C.
The second simulation overlaid that same weather data with a «pseudo
global warming» technique using an accepted scenario that assumes a 2 - to 3 - degree increase in
average temperature, and a doubling
of atmospheric carbon dioxide.
Their findings, based on output from four
global climate models
of varying ocean and atmospheric resolution, indicate that ocean temperature in the U.S. Northeast Shelf is projected to
warm twice as fast as previously projected and almost three times faster than the
global average.
«Northeast US temperatures are decades ahead
of global average: Climate scientists say Northeast will
warm sooner than most
of US.»
In contrast, the consensus view among paleoclimatologists is that the Medieval
Warming Period was a regional phenomenon, that the worldwide nature
of the Little Ice Age is open to question and that the late 20th century saw the most extreme
global average temperatures.
Results
of a new study by researchers at the Northeast Climate Science Center (NECSC) at the University
of Massachusetts Amherst suggest that temperatures across the northeastern United States will increase much faster than the
global average, so that the 2 - degrees Celsius
warming target adopted in the recent Paris Agreement on climate change will be reached about 20 years earlier for this part
of the U.S. compared to the world as a whole.
Without any action, the world is on track to achieve at least 4 degrees C
warming of global average temperatures by 2100, as the world hits 450 parts - per - million
of greenhouse gases in 2030 and goes on to put out enough greenhouse gas pollution to achieve as much as 1300 ppm by 2100.
Global average sea level has risen by roughly 0.11 inch (3 millimeters) per year since 1993 due to a combination
of water expanding as it
warms and melting ice sheets.
Even with more beetles munching on them, an increase
of 2 °C — the current target cap for
global warming — bumps the
average mosquito's probability
of survival into adulthood by 53 %.
Aerosols are already known to reduce
global warming: The vast clouds
of sulfates thrown up in the 1991 eruption
of Mount Pinatubo in the Philippines, for example, reduced
average global temperatures by about half a degree Celsius.
In its annual analysis
of trends in
global carbon dioxide emissions, the Global Carbon Project (GCP) published three peer - reviewed articles identifying the challenges for society to keep global average warming less than 2 °C above pre-industrial l
global carbon dioxide emissions, the
Global Carbon Project (GCP) published three peer - reviewed articles identifying the challenges for society to keep global average warming less than 2 °C above pre-industrial l
Global Carbon Project (GCP) published three peer - reviewed articles identifying the challenges for society to keep
global average warming less than 2 °C above pre-industrial l
global average warming less than 2 °C above pre-industrial levels.
«The long - term baseline temperature is about three tens
of a degree (C)
warmer than it was when the big El Niño
of 1997 - 1998 began, and that event set the one - month record with an
average global temperature that was 0.66 C (almost 1.2 degrees F)
warmer than normal in April 1998.»
The continued top ranking for 2016 may be due in part to El Niño, a cyclical climate event characterized by
warmer - than -
average waters in the equatorial Pacific Ocean, which generated some
of the
global heat that year.
January through August
of 1998 are all in the 14
warmest months in the satellite record, and that El Niño started when
global temperatures were somewhat chilled; the
global average temperature in May 1997 was 0.14 C (about 0.25 degrees F) cooler than the long - term seasonal norm for May.
Surface water in the region is
warming at twice the rate
of the
global average.
Since the 1970s the northern polar region has
warmed faster than
global averages by a factor or two or more, in a process
of «Arctic amplification» which is linked to a drastic reduction in sea ice.
The impacts
of global warming are felt especially in mountainous regions, where the rise in temperatures is above
average, affecting both glacierized landscapes and water resources.
The atmosphere in the polar regions has
warmed at about twice the
average rate
of global warming with Arctic coasts experiencing a rise in the occurrence
of storm surges.
There is some debate about when the «Little Ice Age» — the last time when
global average temperatures were falling — ended, but it is well documented that glaciers started receding around that time as a result
of the relative
warming of the planet.
So the report notes that the current «pause» in new
global average temperature records since 1998 — a year that saw the second strongest El Nino on record and shattered
warming records — does not reflect the long - term trend and may be explained by the oceans absorbing the majority
of the extra heat trapped by greenhouse gases as well as the cooling contributions
of volcanic eruptions.