The Intergovernmental Panel on Climate Change (IPCC), Assessment Report 6 (AR6), stated that the recent climate change is “widespread, rapid, intensifying and unprecedented in thousands of years.” It is further noted: “Climate change is already affecting every region on Earth in multiple ways. The changes we experience will increase with …
There is increasing evidence that the amount of solar radiation incident at the Earth's surface is not stable over the years but undergoes significant decadal variations. Here I review the evidence for these changes, their magnitude, their possible causes, their representation in climate models, and their potential implications for climate …
Particulate solar absorption is a critical factor in determining the value and even sign of the direct radiative forcing of aerosols. The heating to the atmosphere and cooling to the Earth's surface caused by this absorption are hypothesized to have significant climate impacts. We find that anthropogenic aerosols play an …
Studies of chronic health effects due to exposures to particulate matter with aerodynamic diameters ? 2.5 ?m (PM2.5) are often limited by sparse measurements. Satellite aerosol remote sensing data may be used to extend PM2.5 ground networks to cover a much larger area. This study examined the benefits of using …
Central, northern India have a new date with the rains april, May and early June may be the future monsoon months of north and central India. As of now, the official date for the beginning of monsoons is June 29. But there has been a clear increase in rainfall in …
Climate warming has advanced the biological spring and delayed the arrival of biological winter. These changes in the annual cycle of plants and the lengthening of the green-cover season have many consequences for ecological processes, agriculture, forestry, human health, and the global economy. Studies on vegetation-atmosphere interactions and particularly on …
Global climate change is occurring at an accelerating pace, and the global greenhouse gas (GHG) emissions that are forcing climate change continue to increase. Given the present pace of international actions, it seems unlikely that atmospheric composition can be stabilized at a level that will avoid "dangerous anthropogenic interference" with …
This report addresses some of the major questions facing climate change researchers, and how those puzzles are being addressed by NSF-funded activities. Complex computer models are being developed and refined to predict Earth
An unexpected and unwelcome Indian contribution to climate change is beginning to be highlighted: that of so-called black carbon (or, more colloquially, soot) which, according to recent studies, may account for almost 1/5 of global warming
More radiation generally increases vegetation photosynthesis, but field studies show that a given amount of diffuse radiation leads to more fixed carbon than direct radiation. Mercado and colleagues simulate the effect of late twentieth century increases in the diffuse radiation fraction, and find that the terrestrial carbon sink is enhanced …
educing emissions of black carbon and other short-lived pollutants that contribute to global warming could buy the world crucial time while governments begin the slow overhaul of global energy systems that will be required to reduce emissions of CO2, climate modelers reported in Nature Geosciences.
Fundamental to the onset of the Indian Summer Monsoon is the land-sea thermal gradient from the Indian Ocean to the Himalayas-Tibetan Plateau (HTP). The timing of the onset is strongly controlled by the meridional tropospheric temperature gradient due to the rapid pre-monsoon heating of the HTP compared to the relatively …
Greenhouse gases (GHGs) warm the surface and the atmosphere with significant implications for rainfall, retreat of glaciers and sea ice, sea level, among other factors. About 30 years ago, it was recognized that the increase in tropospheric ozone from air pollution (NOx, CO and others) is an important greenhouse forcing …
Traffic is one of the major sources of harmful airborne particles worldwide. To relate exposure to adverse health effects it is important to determine the deposition probability of the inhaled particles in the human respiratory tract. The size-dependent deposition of 12?580 nm particles was measured with a novel setup in …
WASHINGTON - Visibility on clear days has declined in much of the world since the 1970s thanks to a rise in airborne pollutants, scientists said on Thursday. They described a "global dimming" in particular over south and east Asia, South America, Australia and Africa, while visibility remained relatively stable over …
An aerosol is a suspension of fine particles in a gas, usually air, and is generally taken to include both solid and liquid particles with dimensions ranging from a few nanometers up to around 20 micrometers in diameter. This paper presents an overview of the various physical and chemical characteristics …
Black carbon (BC), a component of soot, is a potent climate- forcing agent and has been estimated to be the second largest contributor to global warming after carbon dioxide (CO2). Thus, addressing BC emissions should be considered an essential element of any global warming mitigation strategy. In fact, because BC …
Transport affects climate directly and indirectly through mechanisms that cause both warming and cooling of climate, and the effects operate on very different timescales. The authors calculate climate responses in terms of global mean temperature and find large differences between the transport sectors with respect to the size and mix …
Aerosols above the Himalaya may alter regional thermostat nano-sized pollutants were for the first time found reacting with each other above the Himalaya. Scientists from the Universite Blaise Pascal, France, said these ultra-fine pollutants are combining to form aerosols
