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\begin{document}

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\section*{Carbon emissions}

\hypertarget{contents}{}\section*{{Contents}}\label{contents}

\noindent\hyperlink{Quick}{Quick figures}\dotfill \pageref*{Quick} \linebreak
\noindent\hyperlink{CarbonVersusCarbonDioxide}{Carbon versus carbon dioxide}\dotfill \pageref*{CarbonVersusCarbonDioxide} \linebreak
\noindent\hyperlink{units}{Units}\dotfill \pageref*{units} \linebreak
\noindent\hyperlink{2018_data}{2018 data}\dotfill \pageref*{2018_data} \linebreak
\noindent\hyperlink{2010_data}{2010 data}\dotfill \pageref*{2010_data} \linebreak
\noindent\hyperlink{2007_data}{2007 data}\dotfill \pageref*{2007_data} \linebreak
\noindent\hyperlink{2010_data_from_the_german_federal_government}{2010 Data from the German Federal Government}\dotfill \pageref*{2010_data_from_the_german_federal_government} \linebreak
\noindent\hyperlink{2008_iea_data}{2008 IEA data}\dotfill \pageref*{2008_iea_data} \linebreak
\noindent\hyperlink{usa}{USA}\dotfill \pageref*{usa} \linebreak
\noindent\hyperlink{germany}{Germany}\dotfill \pageref*{germany} \linebreak
\noindent\hyperlink{china}{China}\dotfill \pageref*{china} \linebreak
\noindent\hyperlink{historical_carbon_emissions}{Historical carbon emissions}\dotfill \pageref*{historical_carbon_emissions} \linebreak
\noindent\hyperlink{future_carbon_emissions}{Future carbon emissions}\dotfill \pageref*{future_carbon_emissions} \linebreak


\hypertarget{Quick}{}\subsection*{{Quick figures}}\label{Quick}

\begin{itemize}%
\item In 2011, burning fossil fuels, cement manufacture, land-use change and deforestation put \textbf{10.4$\pm$1 billion tonnes of carbon} (GtC) into the atmosphere, according to the \href{http://www.globalcarbonproject.org/carbonbudget/12/hl-full.htm}{Global Carbon Project}. This corresponds to \textbf{38.1 billion tonnes of carbon dioxide} (GtCO).


\item In 2011 the world's population was \textbf{\href{http://www.prb.org/pdf10/10wpds_eng.pdf}{7 billion}}, so carbon emissions amounted to \textbf{1.5 tonnes of carbon per person}, or \textbf{5.45 tonnes of carbon dioxide per person}.


\item In 2011, \href{http://www.globalcarbonproject.org/carbonbudget/12/hl-full.htm}{9.5$\pm$0.5 billion tonnes of carbon emissions were due to fossil fuels and cement manufacture} while \href{http://www.globalcarbonproject.org/carbonbudget/12/hl-full.htm}{0.9$\pm$0.5 billion tonnes were due to land-use change and deforestation}.


\item Including land-use change, deforestation and cement manufacture, carbon emissions have grown as follows, with a dip from 2008 to 2009:



\end{itemize}
\begin{tabular}{l|l}
year&gigatonnes of carbon\\
\hline 
2010&10.4\\
2010&10.0\\
2009&9.28\\
2008&9.45\\
2007&9.31\\
2006&9.22\\
\end{tabular}

\begin{itemize}%
\item For a high-resolution image showing 2009 carbon emissions by country, click here:

\end{itemize}
\begin{itemize}%
\item For annual CO emissions listed per capita by country from 1990 to 2011, go \href{http://edgar.jrc.ec.europa.eu/overview.php?v=CO2ts_pc1990-2011}{here}. For country totals, go \href{http://edgar.jrc.ec.europa.eu/overview.php?v=CO2ts1990-2011}{here}. For all greenhouse gas per capita emissions by country, go \href{http://edgar.jrc.ec.europa.eu/overview.php?v=GHGts_pc1990-2010}{here}, and for country totals of these go \href{http://edgar.jrc.ec.europa.eu/overview.php?v=GHGts1990-2010}{here}.


\item For detailed data on carbon emissions in 2011, see the \href{http://www.globalcarbonproject.org/carbonbudget/12/files/CarbonBudget2012.pdf}{Global Carbon Budget 2012} put out by the \href{http://www.globalcarbonproject.org/}{Global Carbon Project}.


\item For more data, visit \href{http://co2now.org/Current-CO2/CO2-Now/global-carbon-emissions.html}{CO2Now}.


\item Since 2009, developing countries have been emitting more carbon dioxide than developed countries, and China now emits more than the US. However, the US emits much more carbon per capita than China. NEED FIGURES.


\item US carbon emissions from energy production have been dropping since 2009, and have now dropped to 1992 levels:



\end{itemize}
\hypertarget{CarbonVersusCarbonDioxide}{}\subsection*{{Carbon versus carbon dioxide}}\label{CarbonVersusCarbonDioxide}

Be careful: some people talk about carbon while others talk about carbon dioxide. When you burn a ton of carbon you get about 3.67 tons of carbon dioxide. Neglecting this can cause big mistakes:

$\bullet$ Joe Romm, 

Just remember: C has atomic mass 12, O has atomic mass 16, so CO has atomic mass 12+16+16=44, so a molecule of carbon dioxide is

\begin{displaymath}
44/12 = 3.666...
\end{displaymath}
times as heavy as the atom of carbon that was burned to form it.

\hypertarget{units}{}\subsection*{{Units}}\label{units}

Scientists use \textbf{GtC} as an abbreviation for `gigatonne of carbon'. A \textbf{gigatonne} is a billion ($10^9$) metric tons. A metric ton or \textbf{tonne} is about 10\% bigger than an American ton, but if you're just trying to get rough idea of things and you're used to American units, you don't need to worry about this too much.

A gigatonne is also $10^{15}$ grams, also known as a \textbf{petagram}.

\hypertarget{2018_data}{}\subsection*{{2018 data}}\label{2018_data}

In 2018, global CO emissions due to fossil fuels and cement manufacture was \textbf{10.1 billion tonnes of carbon} (GtC), which corresponds to \textbf{\href{http://folk.uio.no/roberan/GCB2018.shtml}{37.1 billion tonnes of carbon dioxide}} (GtCO).

By the end of 2018 the world's population was \href{http://www.worldometers.info/world-population/}{7.67 billion}, so carbon emissions amounted to \textbf{1.31 tonnes of carbon per person}, or \textbf{4.78 tonnes of carbon dioxide per person.}

\hypertarget{2010_data}{}\subsection*{{2010 data}}\label{2010_data}

Including land-use change, deforestation and cement manufacture, in 2010 emissions reached \textbf{10.0 billion tonnes of carbon} (GtC), which corresponds to \textbf{\href{http://co2now.org/Current-CO2/CO2-Now/global-carbon-emissions.html}{36.7 billion tonnes of carbon dioxide}} (GtCO).

In 2010 the world's population was \href{http://www.prb.org/pdf10/10wpds_eng.pdf}{6.892 billion}, so carbon emissions amounted to \textbf{1.45 tonnes of carbon per person}, or \textbf{5.32 tonnes of carbon dioxide per person}.

\hypertarget{2007_data}{}\subsection*{{2007 data}}\label{2007_data}

In 2007 people on the Earth burnt \textbf{8 gigatonnes of carbon}. Since the population was roughly 6.6 billion, this means the average person burnt \textbf{1.2 tonnes of carbon}. But the average American burnt \textbf{5.2 tonnes}, while the average Chinese burnt \textbf{1.3 tonnes}, and most people burnt less.

This chart lists the carbon dioxide emissions of countries worldwide:

\begin{itemize}%
\item \href{http://en.wikipedia.org/wiki/List_of_countries_by_carbon_dioxide_emissions}{List of countries by carbon dioxide emissions}, Wikipedia.

\end{itemize}
This chart includes only CO emitted by fossil fuel burning and cement manufacture, not deforestation, change in [[Land use|land use]], etc. Methane and other [[greenhouse gases]] are not included. Currently the list is based on data from 2007, taken from this report:

\begin{itemize}%
\item United Nations Statistics Division, Millennium Development Goals indicators: Carbon dioxide emissions (CO2), thousand metric tonnes of CO (collected by CDIAC).

\end{itemize}
One can also see per capita figures here, apparently computed using information from the same source.

\begin{itemize}%
\item \href{http://en.wikipedia.org/wiki/List_of_countries_by_carbon_dioxide_emissions_per_capita}{List of countries by carbon dioxide emissions per capita}, Wikipedia.

\end{itemize}
The entire world is listed as having emitted \textbf{29.3 gigatonnes of carbon dioxide in 2007}. This corresponds to burning \textbf{8 gigatonnes of carbon}. Since the population was roughly 6.6 billion, this means the average person emitted \textbf{4.4 tonnes of carbon dioxide} by burning \textbf{1.2 tonnes of carbon}.

The top eight countries are:

\begin{tabular}{l|l|l|l}
country&gigatonnes of CO in 2007&percentage&tonnes per capita\\
\hline 
China&6.54&22.3\%&4.9\\
United States&5.84&19.9\%&18.9\\
India&1.61&5.50\%&1.4\\
Russia&1.54&5.24\%&10.8\\
Japan&1.25&4.28\%&9.8\\
Germany&0.79&2.69\%&9.6\\
Canada&0.56&1.90\%&16.9\\
United Kingdom&0.54&1.84\%&8.9\\
\end{tabular}

\hypertarget{2010_data_from_the_german_federal_government}{}\subsection*{{2010 Data from the German Federal Government}}\label{2010_data_from_the_german_federal_government}

The following table compares the carbon dioxide emissions of several contries in 1990 and 2004, the data was compiled and provided by the German government:

[[carbon\_emissions\_2004.jpg:pic]]

\hypertarget{2008_iea_data}{}\subsection*{{2008 IEA data}}\label{2008_iea_data}

On 6 October 2010, the International Energy Agency released its own data set (calculated using slightly different methods than CDIAC) for 2008 emissions that listed about 140 countries:

\begin{itemize}%
\item International Energy Agency, \href{http://www.iea.org/co2highlights/co2highlights.pdf}{CO2 Emissions from Fuel Combustion - Highlights}.

\end{itemize}
\hypertarget{usa}{}\subsection*{{USA}}\label{usa}

For US carbon emissions data see:

\begin{itemize}%
\item [[Environmental Protection Agency]], \href{http://www.epa.gov/climatechange/ghgemissions/usinventoryreport.html}{National Greenhouse Gas Emissions Data}.

\end{itemize}
\hypertarget{germany}{}\subsection*{{Germany}}\label{germany}

The following chart shows the emission of $CO_2$ by Germany according to the German federal government (Bundesamt für Statistik):

[[german\_carbon\_emissions.jpg:pic]]

\hypertarget{china}{}\subsection*{{China}}\label{china}

\begin{itemize}%
\item \href{http://www.fas.org/sgp/crs/row/RL34659.pdf}{China’s Greenhouse Gas Emissions and Mitigation Policies}, Congressional Research Service, 10 September 2008.

\end{itemize}
Quoting from the summary of this report:

\begin{quote}%
In June 2007, China released its National Climate Change Program, a plan to address climate change. The Program outlines activities both to mitigate GHG emissions and to adapt to the consequences of potential climate change. Within the Program, perhaps most challenging is China’s goal to lower energy intensity 20\% by 2010. The country fell short of its annual milestones, set in energy policies, in both 2006 and 2007; in July 2008, Premier Wen Jiabao and the State Council warned that meeting its energy intensity and emission reduction goals “remained an arduous task.” Related goals include more than doubling renewable energy use by 2020, expansion of nuclear power, closure of inefficient industrial facilities, tightened efficiency standards for buildings and appliances, and forest coverage expanded to 20\%. The Chinese, and some international observers, claim that China has been more proactive on climate change than some developed countries, though others are cautious of China’s ability to achieve its goals. Meanwhile, Chinese business opportunities in clean and low carbon energy are expanding rapidly.


\end{quote}
\hypertarget{historical_carbon_emissions}{}\subsection*{{Historical carbon emissions}}\label{historical_carbon_emissions}

From this database:

\begin{itemize}%
\item \href{http://www.iiasa.ac.at/web-apps/tnt/RcpDb/dsd?Action=htmlpage&page=welcome}{RCP emissions database}

\end{itemize}
one obtains a total of \textbf{355 GtC of fossil fuel emissions} from preindustrial times to the year 2005, and about \textbf{160 GtC of other emissions} (for example, land use changes), for a grand total of \textbf{510 GtC}.

\hypertarget{future_carbon_emissions}{}\subsection*{{Future carbon emissions}}\label{future_carbon_emissions}

One can't predict the future, but one can make projections based on assumptions. \href{http://www.princeton.edu/~nurban/pubs/moc-projections.pdf}{Nathan Urban's paper with Klaus Keller}, discussed in ``\href{http://math.ucr.edu/home/baez/week304.html}{week304}'' and ``\href{http://math.ucr.edu/home/baez/week305.html}{week305}'', uses this source:

\begin{itemize}%
\item William D. Nordhaus, 2007. The challenge of global warming: Economic models and environmental policy, Technical report, .


\item William D. Nordhaus, , Yale University Press, New Haven, 2008.



\end{itemize}
Based on Nordhaus' work, Urban estimates that in a ``business as usual'' scenario, \textbf{by the year 2300 we will have burnt 4800 gigatonnes worth of of carbon}, compared to the roughly 510 gigatonnes we’ve burned far.

This projection assumes we get desperate for cheap energy and extract not only coal, oil and gas but also all the hard-to-get fossil resources in oil shales and tar sands, all the remaining coal, etc. It does \emph{not} include the [[methane clathrates]] at the bottom of the sea.

Here's a graph from \href{http://www.princeton.edu/~nurban/pubs/moc-projections.pdf}{Urban and Keller's paper}:

In this scenario carbon emissions peak around 2150 at about 23 gigatonnes carbon per year (84 gigatonnes CO). By 2300 they’ve tapered off to about 4 GtC (15 GtCO).

The figure of 4800 gigatons in the year 2300 is not the end of the story, because in his book Nordhaus estimates that \textbf{6000$\pm$1200 gigatonnes of carbon are available to be burnt} (again, not counting methane clathrates).

It's currently estimated that there are somewhere between \textbf{500 and 2500 gigatonnes of carbon in methane clathrates}:

\begin{itemize}%
\item A.V. Milkov, Global estimates of hydrate-bound gas in marine sediments: how much is really out there?, \emph{\href{http://doi:10.1016/j.earscirev.2003.11.002}{Earth-Sci. Rev.}} \textbf{66} (2004). 183–197.

\end{itemize}
These recent figures are much less than earlier estimates.

category:carbon

[[!redirects carbon emissions]] [[!redirects carbon emission]]



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