Most black carbon over Arctic comes from South Asia per James Hansen NASA GISS peer reviewed study, 2005: Great news for those who care about the Arctic, Greenland, or Hawaii. Bad news: Solution doesn't cost much money or require global treaty. Poor and needy could see return of billions of tax dollars starved from them for decades in favor of CO2 scare

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"The largest contribution to BC (black carbon) deposited on Greenland is from south Asia."...[35] From 1980-1995, "BC emissions from developed countries have declined and aircraft are apparently not to blame. However, during this time BC emissions from China and India have nearly doubled."
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 2/25/2005, "Distant origins of Arctic black carbon: A Goddard Institute for Space Studies ModelE experiment," Journal of Geophysical Research Atmospheres, Dorothy Koch and James Hansen
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"1. Introduction" (subhead)

"[11] Several studies, focused more on the outflow from Asia, hint at a potentially significant role for East Asian pollution in the Arctic. Wilkening et al. [2000] reported a significant level of east Asian pollution transported across the Pacific to North America and suggested that this may be an important Arctic source as well. Where there is Asian dust, there is often black carbon, as reported by Perry et al. [1999] who frequently observed black carbon mixed with dust, and sometimes independent of dust, over Hawaii in the springtime. Kaneyasu and Murayama [2000] reported very high levels of BC (>150 ng m⁻³) in the north central Pacific. The BC was associated with high levels of sulfate and not with potassium, indicative of a coal burning source rather than a biomass source. Their analysis indicated that it was derived from Asia, lofted to high altitudes, transported out over the Pacific, where it descended to the surface. A similar transport pathway was presented by Raatz [1985]. VanCuren and Cahill [2002] found substantial levels of Asian dust in decade-long records at elevated sites in North America. They argued that the dust is transported steadily, during all seasons except winter, at altitudes of 500–3000 meters. After further analysis of the data, VanCuren [2003] found the Asian dust is mixed with substantial amounts of combustion products, including elemental carbon. The export of pollutants from Asia has been the topic of recent campaigns, such as the spring 2001 ACE Asia (Aerosol Characterization Experiment) and the spring 2002 NOAA-ITCT 2K2 (Intercontinental Transport and Chemical Transformation 2002) project. During the NOAA-ITCT 2K2, rapid transport of high altitude (>2 km) Asian urban and biomass pollutants and particles across the Pacific was reported [Bertschi et al., 2004]. Matsuki et al. [2003] used aircraft, lidar and trajectory analysis, and Liang et al. [2004] used the GEOS CHEM model, to show that during winter the transport appears to be facilitated by uplift ahead of cold fronts and rapid transport by westerlies; during summer convective uplift also lofts pollution from the boundary layer. During springtime this transport occurs throughout the column primarily between 20–50°N; during summer the transport shifts to higher levels (>2–4 km) and to higher latitudes, 30–60°N. During ACE Asia, Cahill [2003] used elemental analysis and back trajectory to demonstrate the transport of Asian aerosols into Alaska and the sub-Arctic. Biscaye et al. [2000] also reported large amounts of Asian dust transported from Asia across North America, with a reduction of less than a factor of 10 as it crosses North America en route to Greenland. They postulated that Asian aerosol pollutants should have a similar fate. Indeed, significant Asian dust, along with background pollution, was observed in the Arctic during the spring of 1976 [Rahn et al., 1977].

[12] Bowling and Shaw [1992] used thermodynamical argument to indicate that in order for polluted air to reach the Arctic via isentropic flow, low-level haze probably needs to originate from smoke stack injections into dry air; higher-level haze (above 3 km) would need to come from an extremely dry and/or high altitude source, such as a desert. This analysis might be consistent with a mixed dust-pollution source region such as the Asian Steppes. Hot dry biomass burning conditions might also satisfy the thermodynamic requirements.
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[13] We use our global model to examine the degree to which the Arctic is impacted by the more distant south Asian and low-latitude biomass regions which have the largest emissions, compared with the previously studied “Arctic haze” source regions of Europe, Russia and North America....

3.5 Deposition to Greenland...

[35] The model indicates that the largest contribution to BC deposited on Greenland is from south Asia (20–30%), with nearly as much coming from Europe. North America and northern biomass burning contribute 10–20% each. Russia contributes at least 10% over the western portion of Greenland.

4. Discussion

[39] Our global model indicates that most of the black carbon in the present-day Arctic comes from industrial and biofuel sources in south Asia and from biomass burning. Such BC arrives in the Arctic at higher altitudes throughout the year, in contrast with the surface-level springtime haze that is often the focus of Arctic haze studies. We do not imply that most of the BC in these distant regions is transported to the Arctic. On the contrary, according to our model most of south Asian BC remains south of 60°N. However enough of it makes its way north to become the major contributor to Arctic BC, so that about 20–40% of Arctic BC optical thickness comes from south Asia. This region has the largest industrial BC emission, about 21% of the global emission. It contributes about 20% to the lower troposphere winter-spring transport to the Arctic, or Arctic haze, and to surface deposition. Because the south Asian BC tends to travel at higher altitudes, it contributes a higher percentage to optical thickness and radiative forcing (20–40%)....

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[40] Again, most of these [BC] biomass emissions remain at low latitudes and contribute to the BC load there. However, enough of the BC is lofted to higher altitudes, according to the model, to make significant contributions to the Arctic burden. About 60% of the global BC is from southern biomass burning. In the Arctic it contributes substantially to optical thickness and radiative forcing (10–20%)....

[44] The distant sources are generally not considered in studies of pollution in the Arctic. This may be because their contribution to the surface level winter-spring Arctic haze is less than that of Europe and Russia. Transport from south Asia tends to occur at higher altitudes and for a greater portion of the year than traditionally assumed for Arctic haze. In addition, the long-distance transport from south Asia and southern biomass regions may take longer, further limiting these distant sources from trajectory analysis....

[47] Despite the possibility that the model exaggerates long-range transport of aerosols, our results suggest that these distant source regions are probably significant contributors to Arctic BC abundance. The existence of substantial contribution from distant sources is supported by observations such as large BC amount at midlevels of the troposphere, so there is evidence supporting a prominent role for southeast Asian sources in the Arctic. The timing and location of Arctic warming and sea ice loss in the late 20th century is consistent with south Asian sources. According to Baumgardner et al. [2004], BC concentrations in the UT/LS over the Arctic seem to have doubled between 1980 and 1995 (although they also indicate that the early data are highly uncertain). BC emissions from developed countries have declined and aircraft are apparently not to blame. However, during this time BC emissions from China and India have nearly doubled [Novakov et al., 2003]. Also, the model indicates that most of the concentrations in this region of the UT/LS are from south Asia.
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[48] According to the 2002 AMAP Assessment [MacDonald et al., 2003], the past three decades show significant decreases in sea ice thickness and extent. This recent decrease is greatest in spring and fall and occurs in the western Arctic (western North America and Siberia). These observations defy recent modeling efforts, which show the largest impact of increased CO₂ on the Arctic winter rather than summer. [MacDonald et al., 2003]. The pattern of sea ice loss is believed to be linked to the phase of the AO [MacDonald et al., 2003]. However it is interesting that these decades correspond to the increases in BC from south Asia, and that this BC is transported over the Pacific and into the western Arctic, during summer as well as spring. Prior to this, sea ice also decreased during the 1930s–1940s. However this occurred during winter in the eastern part of the Arctic. Again it is interesting to note that during this earlier period, pollution from coal burning in the United States, Europe and Russia [Novakov et al., 2003] would have been transported to the Arctic during winter-spring, and the Eurasian sources would deposit heavily in the eastern Arctic (see Figure 10)."...

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Short lived black carbons are responsible for half of global temperature increase. Can be dealt with using existing laws and technologies, no global treaty needed. Have been ignored by climate scientists and green pressure groups:

5/21/12, "G8: Leaders open up vital new front in the battle to control global warming," UK Telegraph, Geoffrey Lean

"It seems to have gone virtually unnoticed, but the world leaders at the weekend's G8 summit look as if they have taken the biggest step in years in tackling climate change. And it's quite apart from anything to do with carbon dioxide.
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The summit's final communiqué, the Camp David Declaration, supports “comprehensive actions” to reduce “short-lived climate pollutants”. These substances – including black carbon (soot), methane, ground-level ozone, and hydrofluorocarbons – are responsible for about half of global warming. Straightforward measures to address them, a report by the United Nations Environment Programme concluded last year, would delay dangerous climate change by more than three decades, buying crucial time for the much more difficult process of slashing carbon dioxide emissions.
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More important still, the measures would save some 2.4 million lives a year, mainly by cutting the inhalation of soot, chiefly emitted by vehicle diesel engines and by the inefficient wood and dung burning cookstoves used by most of the world's poorest people – and increase grain harvests, at present hit by pollution, by 52 million tons a year.
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While the international climate negotiations drag on, these pollutants can be reduced through existing national laws and regulations, using technologies that are already available. And many climate sceptics agree on the importance of doing so: Senator James Inhofe, who pioneered Republican rejection of action to curb carbon dioxide, supports it on black carbon, while Canada – which caused controversy this winter by quitting the Kyoto Protocol – has been in the forefront of countries urging an assault on such the short-lived agents of climate change.
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The G8's endorsement of action at the weekend is a triumph for the small Institute for Governance and Sustainable Development (IGSD), which has been campaigning for action on the pollutants while most climate scientists and green pressure groups have ignored them. In just a few short years it has brought the issue from invisibility to the agendas of the world's most powerful leaders. In February six governments – including the US, Canada and Mexico – launched a five year programme to tackle them, and the rest of the G8 has now signed up to it. And it commissioned the World Bank to produce a report on how it can integrate ways of reducing them into its activities.
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The leaders also reaffirmed their commitments to limiting the increase in the world's temperature to less than two degrees centigrade over pre-industrial levels and phasing out subsidies for fossil fuels – and welcomed December's Durban climate summit as “a significant breakthrough” towards reaching international agreements on cutting carbon dioxide by 2015.
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It will remain important to continue this international effort. But as Durwood Zaelke, the IGSD president puts it “the solution-orientated approach” of the programme to address the short-lived pollutants can “show the world it is possible to start meeting the climate challenge.”"