A linear warming trend plus natural cycles can be mistaken for a step function, but physically the global warming is caused by an external radiative forcing (
i.e. human greenhouse gas emissions).
Not exact matches
Granted, there are more benefits to reducing particulate and
greenhouse gas emissions than just climate change,
i.e. PM 2.5 which can be stuck in the
human lung and cause cancer / respiratory issues, SO2 which contributes to acid rain (we've already eliminated the majority of this problem), as well as soot (nobody wants the surrounding area covered in ash).
Human water vapour emissions are irrelevant, as water vapour is in dynamic equilibrium with ocean water, an equilibrium controlled by global mean temperature,
i.e., other
greenhouse gases etc..
But the IPCC concerns itself with consideration of anthropogenic (
i.e. man - made) global warming (AGW) as a result of emissions of
greenhouse gases (notably carbon dioxide, CO2) from
human activities.
First, while the early 20th century warming was likely predominantly naturally - caused (
i.e. low volcanic activity and increasing solar activity), there was also a significant
human contribution as
greenhouse gas emissions began to ramp up.
The reduction in nighttime cooling that leads to this bias may indeed be the result of
human interference in the climate system (
i.e., local effects of increasing
greenhouse gases or
human effects on cloud cover), but through a causal mechanism different than that typically assumed.
Also, the basic theory behind the scientific argument
i.e. increasing
greenhouse gases in the atmosphere due to
humans burning fossil fuels will lead (and is leading) to global warming which will change the climate, is not being stated often enough in the media.
The largest climate forcing today,
i.e. the greatest imposed perturbation of the planet's energy balance [1,2], is the
human - made increase in atmospheric
greenhouse gases (GHGs), especially CO2 from the burning of fossil fuels.
We support educating the public and policymakers in government and industry about the harmful
human health effects of global climate change, and about the immediate and long - term health benefits associated with reducing
greenhouse gas emissions (
i.e., heat - trapping pollution) and taking other preventive and protective measures that contribute to sustainability.
The solar contribution to recent temperature change is probably minimal and / or negative (
i.e., the sun has probably caused cooling, but
human increases in
greenhouse gasses have overwhelmed that small cooling to cause a net warming).