Climate models are not designed to capture record daily highs and lows with precision, and it remains impossible to know future human actions that will determine the level
of future greenhouse gas emissions.
Dr Hawkins said: «Putting a precise date on when we see the first days or weeks that are «ice - free» is unwise because of the chaotic nature of the climate system and uncertainties
in future greenhouse gas emissions.»
Contemporary global mean sea level rise will continue over many centuries as a consequence of anthropogenic climate warming, with the detailed pace and final amount of rise depending substantially
on future greenhouse gas emissions.
In particular,
future greenhouse gas emissions depend on societal choices, policies, and technology advancements not yet made, and climate - change impacts depend on both the amount of climate change that occurs and the effectiveness of development in reducing exposure and vulnerability.
To simulate future hurricanes, Reindert Haarsma of the Royal Netherlands Meteorological Institute in De Bilt and colleagues ran a detailed climate model for 2094 to 2098, assuming
modest future greenhouse gas emissions.
Methods: A global collaboration of scientists responded to a request from the Intergovernmental Panel on Climate Change, and generated a set of four scenarios to
represent future greenhouse gas emissions and land use change.
Unchecked future greenhouse gas emissions, particularly of carbon dioxide from the burning of fossil fuels, will almost certainly lead to additional climate impacts such as further global warming, continued sea level rise, greater rainfall intensity, more serious and pervasive droughts, enhanced heat stress episodes, ocean acidification, and the disruption of many biological systems.
To help our client countries mitigate current and
future greenhouse gas emissions while at the same time stimulating development, the Bank is using a variety of financial instruments and programs to target different sectors of the economy.
They compared historical weather records, an 1,800 - year - long simulation of the climate pre-Industrial-Revolution, and 40 simulations of climate change from 1920 to 2100 (assuming
high future greenhouse gas emissions).
Some of this warming will occur even
if future greenhouse gas emissions are reduced, because the Earth system has not yet fully adjusted to environmental changes we have already made.
«With a high scenario
for future greenhouse gas emissions, the largest warming occurs over the high latitudes of the Northern Hemisphere, but all land areas warm dramatically,» remarked Field
«Climate models can easily make assumptions about reductions
in future greenhouse gas emissions and project the implications, but they do this with no rational basis for human responses,» Gross said.
Where the uncertainty comes in, she said, is in projections of future warming — which depend in part on the world's
future greenhouse gas emissions, as well as scientists» understanding of the physics of warming and the biogeochemical cycles of the Earth.
A new study found China's power plants will account for 42 percent of the world's
future greenhouse gas emissions.
How the Antarctic ice sheet evolves in response to
future greenhouse gas emissions is a looming concern for coastal populations and ecosystems.
This rise is larger and probably faster than any such change over the past 9,000 years.Climate models are far from perfect, and they rely on projections of
future greenhouse gas emissions that are far from certain.
Future sea level rise primarily depends on
our future greenhouse gas emissions.
The amount of
future greenhouse gas emissions is a key variable.
Thus regardless of
future greenhouse gas emissions, some degree of human - induced climate change will occur for at least the next 100 years.
These global climate models typically receive inputs from neoclassical economic and human demographic models for calculations of
future greenhouse gas emissions.
However, the model results are important because they show that, in all likely scenarios of
future greenhouse gas emissions, record daily highs should increasingly outpace record lows over time.
Until this is achieved, it will be hard to be specific about the societal impacts of
future greenhouse gas emissions, an uncertainty that, it can be argued, should make us even more cautious about disturbing the system.
There are simply too many unknowns involved in the future evolution of climate, such as how much humans will curb
their future greenhouse gas emissions.
Or that average global temperatures could increase by as much as 11.5 °F by 2100, depending on the level of
future greenhouse gas emissions, according to recent climate models.
They say the range is large because it is difficult to predict future eruptions and
future greenhouse gas emissions.
Whether probabilities can be applied to describe future social choice, in particular uncertainties in
future greenhouse gas emissions, has also been the subject of considerable scientific debate (e.g., Allen et al., 2001; Grubler and Nakićenović, 2001; Lempert and Schlesinger, 2001; Pittock et al., 2001; Reilly et al., 2001; Schneider, 2001, 2002).