Monitoring of GHG at atmosphere and different ecosystem

Greenhouse gas monitoring is the direct measurement of greenhouse gas emissions and levels. There are several different methods of measuring carbon dioxide concentrations in the atmosphere, including infrared analyzing and manometry. Methane and nitrous oxide are measured by other instruments. Greenhouse gases are measured by satellite monitoring such as the Orbiting Carbon Observatory and networks of ground stations such as the Integrated Carbon Observation System.

Carbon dioxide monitoring

Manometry

Manometry is a key measurement tool for atmospheric carbon dioxide by first measuring the volume, temperature, and pressure of a particular amount of dry air. The air sample is dried by passing it through multiple dry ice traps and then collecting it in a five liter vessel. The temperature is taken via a thermometer and pressure is calculated using manometry. Then, liquid nitrogen is added, causing the carbon dioxide to condense and become measurable by volume. The ideal gas law is accurate to 0.3% in these pressure conditions.

Infrared gas analyzer

Infrared analyzers were used at Mauna Loa Observatory and at Scripps Institution of Oceanography between 1958 and 2006. IR analyzers operate by pumping an unknown sample of dry air through a 40 cm long cell. A reference cell contains dry carbon dioxide-free air. A glowing nichrome filament radiates broadband IR radiation which splits into two beams and passes through the gas cells. Carbon dioxide absorbs some of the radiation, allowing more radiation that passes through the reference cell to reach the detector than radiation passing through the sample cell. Data is collected on a strip chart recorder. The concentration of carbon dioxide in the sample is quantified by calibrating with a standard gas of known carbon dioxide content.

Titrimetry

Titrimetry is another method of measuring atmospheric carbon dioxide that was first used by a Scandinavian group at 15 different ground stations. They began passing a 100.0 mL air sample through a solution of barium hydroxide containing cresolphthalein indicator.

Methane gas monitoring

Differential absorption lidar

Range-resolved infrared differential absorption lidar (DIAL) is a means of measuring methane emissions from various sources, including active and closed landfill sites. The DIAL takes vertical scans above methane sources and then spatially separates the scans to accurately measure the methane emissions from individual sources. Measuring methane emissions is a crucial aspect of climate change research, as methane is among the most impactful gaseous hydrocarbon species.

Nitrous oxide monitoring

Atmospheric Chemistry Experiment‐Fourier Transform Spectrometer (ACE-FTS)

Nitrous oxide is one of the most prominent anthropogenic ozone-depleting gases in the atmosphere. It is released into the atmosphere primarily through natural sources such as soil and rock, as well as anthropogenic process like farming. Atmospheric nitrous oxide is also created in the atmosphere as a product of a reaction between nitrogen and electronically excited ozone in the lower thermosphere.

The Atmospheric Chemistry Experiment‐Fourier Transform Spectrometer (ACE-FTS) is a tool used for measuring nitrous oxide concentrations in the upper to lower troposphere. This instrument, which is attached to the Canadian satellite SCISAT, has shown that nitrous oxide is present throughout the entire atmosphere during all seasons, primarily due to energetic particle precipitation. Measurements taken by the instrument show that different reactions create nitrous oxide in the lower thermosphere than in the mid to upper mesosphere. The ACE-FTS is a crucial resource in predicting future ozone depletion in the upper stratosphere by comparing the different ways in which nitrous oxide is released into the atmosphere. 

Satellite monitoring

Orbiting Carbon Observatory (OCO, OCO-2, OCO-3)

The Orbiting Carbon Observatory (OCO) was first launched in February of 2009 but was lost due to launch failure. The Satellite was launched again in 2014, this time called the Orbiting Carbon Observatory-2, with an estimated lifespan of about two years. The apparatus uses spectrometers to take 24 carbon dioxide concentration measurements per second of Earth's atmosphere. The measurements taken by OCO-2 can be used for global atmospheric models and will allow scientists to locate carbon sources when its data is paired with wind patterns. The Orbiting Carbon Observatory-3 was planned to launch in 2018 that was stand alone on the International Space Station (ISS) but it was cancelled.

Greenhouse Gases Observing Satellite (GOSat)

Satellite observations provides accurate readings of carbon dioxide and methane gas concentrations for short-term and long-term purposes in order to detect changes over time. The goals of this satellite, released in January of 2009, is to monitor both carbon dioxide and methane gas in the atmosphere, and to identify their sources. GOSat is a project of three main entities: the Japan Aerospace Exploration Agency (JAXA), Japan’s  Ministry of the Environment (MOE), and the National Institute for Environmental Studies (NIES).

Ground stations

Integrated Carbon Observation System (ICOS)

The Integrated Carbon Observation System was established in October 2015 in Helsinki, Finland as a European Research Infrastructure Consortium (ERIC). The main task of ICOS is to establish an Integrated Carbon Observation System Research Infrastructure (ICOS RI) that facilitates research on greenhouse gas emissions, sinks, and their causes. The ICOS ERIC strives to link its own research with other greenhouse gas emissions research to produce coherent data products and to promote education and innovation

A comprehensive GHG inventory for India is within reach

Maintaining an inventory of greenhouse gas emissions is a fundamental building block in a country’s climate policy. This is why, in accordance with Articles 4 and 12 of the Climate Change Convention (and the relevant COP decisions), Parties to the UNFCCC submit national greenhouse gas (GHG) inventories to the Climate Change secretariat every two years. This biennial reporting requirement applies to both, developed and developing countries (applicable since 2014 for the latter), although Least Developed Countries (LDCs) and Small Island Developing States (SIDS) are allowed to submit them at their own discretion.

India’s first updated numbers were made available in a 2010 inventory published by the Union Ministry of Environment, Forest and Climate Change (MoEF&CC). It showed trends in GHG emissions for the years 1994-2007. It found that the total GHG emissions without Land use, land-use change, and forestry (LULUCF) had grown from approximately 1,252 Mt CO₂e in 1994 to approximately 1,905 Mt CO₂e in 2007, at a compounded annual growth rate (CAGR) of 3.3 per cent and (2.9 per cent with LULUCF). Sectors with significant growth in GHG emissions were cement production (6.0 per cent), electricity generation (5.6 per cent) and transport (4.5 per cent).

India submitted its first Biennial Update Report (BUR) in 2015. The top line inventory figure is that India’s GHG emissions (including land use change and forestry) increased from “1,301.2  Mt  CO₂ eq  in  2000 to 1,884.3  Mt  CO₂ eq during 2010, an increase of 583.1 Mt CO₂ eq during the 10 year period”. The report also notes that the GDP of the country roughly doubled and the population increased by about 18 per cent during this period. The data in the BUR, however, is available only from 2000, up until the year 2010.

Since India has not submitted a second BUR, we are also in the dark regarding the last eight years, which have seen significant economic and population growth as well as the beginnings of a national climate policy. There is an inherent difficulty in collecting economy-wide data. However, it is noteworthy that Israel, which also submitted its first BUR in 2015, had data for the year 2013. It is clear that there are limitations in India’s current capacity to collect such data systematically.

This is evident from the description of the data collection process in India’s BUR. It notes that MoEF&CC assigned twelve institutions to carry out the inventory preparation exercise “as per their expertise in the respective sectors”— Central Institute of Mining and Fuel Research, Dhanbad, Central Road Research Institute, New Delhi, Confederation of Indian Industry, New Delhi, Forest Survey of India, Dehradun, Indian Agricultural Research Institute, New Delhi, Indian Institute of Management, Ahmedabad, Indian Institute of Petroleum, Dehradun, Indian Institute of Science, Bengaluru, National Dairy Research Institute, Karnal, National Environmental Engineering Research Institute, Nagpur, National Physical Laboratory, New Delhi and the National Remote Sensing Centre, Hyderabad.

This is, in part, a reflection of the mammoth nature of the task. However, the US GHG inventory is published annually (since 1990) by the sole responsible agency —the Environment Protection Agency or EPA. Having the relevant expertise to conduct an inventory exercise is important, but it is equally important that one institution is tasked with preparing the inventory, in order to make it more than an ad hoc activity. The relevant experts must then be placed with, or made available to, this institution.

Assuming a single agency is tasked with preparing such reports, it must be able to draw from data across Government departments at national and state level. However, as India’s BUR acknowledges, “India does not have any GHG monitoring and mitigation assessment-related domestic Measurement, Reporting and Verification arrangements presently”. Monitoring and review of various government schemes, projects and programmes (many of which have direct GHG implications) is confined to financial and physical parameters that are embedded in the project design. There is no assessment of GHG emissions and mitigation achieved. The picture is further complicated by the fact that, within economic sectors, multiple agencies and departments collect different segments of data that have relevance for a GHG inventory.

The challenge has been taken up, to an extent, by civil society initiatives such as “GHG Platform India”, which has data for economy-wide emissions and emissions from the electricity, industry, Agriculture, Forestry and Other Land Use (AFOLU) and waste sectors for the time period 2005-2013. As with government efforts, sources of data for this initiative are also fragmented. For the electricity sector, for example, the Platform pulls data from the General Review reports of the Central Electricity Authority, statistical publications from the Union Ministries of Petroleum and Natural Gas, Coal, Statistics and Programme Implementation and the National Sample Survey Organisation’s (NSSO) household expenditure surveys. In addition, corroboration and plugging of gaps was based on research studies from IIM-Ahmedabad, ICF International, Infrastructure Development and Finance Company (IDFC) and other databases such as The Energy Resource Institute’s TEDDY Yearbooks.

Also noteworthy is the CAIT Climate Data Explorer, which has annual GHG emission data for India from 1990, but only through 2014. A comprehensive up-to-date GHG inventory is, therefore, still needed in India. It will not necessarily require new resources, but better co-ordination and commitment of existing resources. For the trouble, however, Indian climate policy would have a firm quantitative footing from which to raise ambition.

Measuring greenhouse gases from the land

In New Zealand, most methane emissions come from burps from ruminant animals – sheep, cows, deer – and from their manure. Measuring methane emissions from animals has a few challenges as nearly all of the country’s animals are kept outdoors. Respiration chambers provide the most precise measurement methods. The chambers are acrylic compartments that continuously sample the air and the amount of methane the animals produce. Scientists briefly house animals in the chambers to measure different feeds, effectiveness of treatments and animals with different genotypes. Portable chambers and monitoring yokes measure burps/emissions when the animals are out in the paddocks. Animal experiments like these are subject to strict ethics approval.

Animal urine patches

Animal urine patches are patches of nutrient-rich grass (dark green) caused by urine deposits of cows (and sheep to a lesser extent). These patches contain concentrated amounts of nitrogen.

Nitrous oxide emissions come primarily from urine patches in paddocks and less so from dung and fertilisers. Soil chambers are the traditional method for measuring N₂O. These small enclosures effectively measure gases given off by the soil. Each chamber covers a small area of pasture, so they are unable to measure emissions coming from an entire paddock.

Micrometeorology is a way of measuring nitrous oxide at a larger scale. Sensors measure gas concentrations multiple times per second. They help to check whether small-scale measurements from individual animals or soil chambers are representative of an entire herd or flock.

Measuring ancient greenhouse gases

New Zealand scientists, like others around the globe, also measure greenhouse gas levels from prior centuries. Although they cannot go back in time, the scientists can use air bubbles in ancient ice cores to measure atmospheric gases at the time the ice was formed. This information helps scientists link ancient climate conditions with their causes and effects.

Wetlands are key for accurate greenhouse gas measurements in the Arctic

For the 10-year period from 2006 to 2015, the tundra of Western Russia had likely remained a “net carbon sink”, sequestering atmospheric CO₂ through plant uptake and growth. This signal varied little between all the years and was particularly strong in wetlands, which were “hotspots” for carbon uptake. Wetlands are also “hotspots” of methane emissions in the region, making the identification of wetlands essential for determining the regional carbon budget.

Since the Arctic is rapidly warming, with stronger effects than observed elsewhere in the world. The Arctic regions are particularly important with respect to climate change, as permafrost soils store huge amounts of the Earth’s soil carbon. Warming of Arctic soils and thawing of permafrost can have substantial consequences for the global climate, as the large C stored in soils could be released to the atmosphere as the greenhouse gases carbon dioxide and methane. The release of these heat-trapping gases, in turn, has the potential to further enhance climate warming.

Determining whether the Arctic is continuing to take up carbon from the atmosphere or instead releasing it to the atmosphere is an urgent research priority, particularly as the climate warms. A new study by researchers at the University of Eastern Finland now provides the first estimate of regional carbon budget for tundra in Western Russia for the 10-year period from 2006 to 2015. The researchers found that over the past decade, the region has likely remained a net carbon sink, sequestering atmospheric CO₂ through plant uptake and growth. This signal varied little between all the years and was particularly strong in wetlands, which were "hotspots" for carbon uptake. Wetlands are also "hotspots" of methane emissions in the region, making the identification of wetlands essential for determining the regional carbon budget. However, it remains challenging to determine the area of tundra wetlands at broader scales because they can be difficult to identify from satellite images, requiring many measurements on the ground to verify their locations.

Due to harsh winter conditions, making measurements throughout the year in tundra sites is exceptionally difficult. Few measurements have been made, making the assessment of the Arctic carbon balance challenging. Previously, researchers from the Biogeochemistry research group at the University of Eastern Finland have measured carbon balance in Western Russia during four growing seasons, but also during more rarely studied periods the spring, fall and winter, laying the groundwork for a longer-term assessment of whether the site has continued to take up atmospheric carbon.

Methane is a greenhouse gas that is less prevalent than carbon dioxide, but it traps radiation at more than 20 times the efficiency of carbon dioxide. And studies have shown that wetlands contribute between 15 percent and 45 percent of global methane emissions.

In a 2013 report, the National Oceanic and Atmospheric Administration projected that winter precipitation will increase by as much as 20 per cent and summer precipitation will decrease by as much as 12 per cent to impact the natural fluxes in the production of methane gas.

The effect of vascular plants (cattails) on the wetlands’ gas emissions. Vascular plants contain tissues that transport water, nutrients, and gases throughout the plants and into the atmosphere. Vascular plants can also act as a conduit for the gases in the soil to be released into the atmosphere. The cattails have an effect on the amount of methane being released into the atmosphere.

Wetlands serve as a “huge sink” for collecting and filtering pollutants from the environment. “However, wetlands are also the largest natural source of methane, so we have an environmental tradeoff,”

To capture the gases emitted from the wetlands, gas sampling chambers were constructed from PVC pipe, along with 18 PVC “collars” mounted in the wetland’s soil. Half of the collars contain cattails, while the other half are placed over soil without vegetation. Every week, she mounts the chambers on the collars and takes samples of gases from the sampling chambers at four-hour intervals, along with soil samples to measure the moisture of the soil.

The samples are then analyzed, using gas chromatography to measure the fluxes in greenhouse gases.

The greenhouse gas emissions from a Swedish wetland, constructed to decrease nutrient content in sewage treatment water. To evaluate the effect of the construction in terms of greenhouse gas emissions we carried out ecosystem-atmosphere flux measurements of CO₂, CH₄ and N₂O using a closed chamber technique.

To evaluate the importance of vascular plant species composition to gas emissions the measurement plots were distributed over the three dominating plant species at the field site, i.e., Typha latifolia, Phragmites australis and Juncus effusus. The fluxes of CO₂ (total respiration), CH₄ and N₂O from vegetated plots ranged from 1.39 to 77.5 (g m⁻² day⁻¹), −377 to 1387 and −13.9 to 31.5 (mg m⁻² day⁻¹) for CO₂, CH₄ and N₂O, respectively. Presence of vascular plants lead as expected to significantly higher total respiration rates compared with un-vegetated control plots.

Furthermore, it was found that the emission rates of N₂O and CH₄ was affected by presence of vascular plants and tended to be species-specific. The integrated greenhouse warming effect of the emissions was assessed using a Global Warming Potential over a 100-year horizon (GWP₁₀₀) and it corresponded to 431 kg CO₂ equivalents m⁻² day⁻¹. Assuming a 7-month season with conditions similar to the study period this is equal to 90 tonnes of CO₂ equivalents annually. N₂O emissions were responsible for one third of the estimated total greenhouse forcing. Furthermore, it was found that the emission from the forested bog that was the precursor land to Magle constructed wetland amounted to 18.6 tonnes of CO₂ equivalents annually. Hence, the constructed wetland has increased annual greenhouse gas emissions by 71.4 tonnes of CO₂ equivalents for the whole area. The result indicated that management processes in relation to wetland construction projects must consider the primary function of the wetland in decreasing eutrophication, in relation to other positive aspects on for instance plant and animal life and recreation as well as possible negative climatic aspects of increased emissions of CH₄ and N₂O.

Sixty of the world’s space agencies have come together for the first time to collectively monitor human-induced greenhouse gas emissions. Brought together by the Indian Space Research Organisation (ISRO) and the French Space Agency (CNES) in New Delhi on April 3, the countries agreed to establish “an independent, international system” to collate data from their satellites. The declaration came into effect on May 16, 2016.

"It is overwhelming to see the unilateral support of all space agencies to use space inputs for monitoring climate change,” said ISRO Chairperson A S Kiran Kumar in an official release. “Earth observation satellites provide a vital means of obtaining measurements of the climate system from a global perspective.” 

Out of 50 essential climate variables being monitored today, 26 of them can be measured only from space—aerosols (particles from natural sources and human activities), ocean surface temperature, rising sea level, sea ice extent, glaciers, cloud structure and greenhouse gas concentrations in all layers of the atmosphere.

Japan's GoSat and the US OCO-2 satellites are in orbit measuring carbon emissions. China is developing its own TanSat and France is working on the MicroCarb satellite to survey CO₂ emissions. 

By linking countries’ satellites to track emissions and record information, a combination of comparative data will be formulated over time. It is a transition towards closely coordinated and easily accessible “big space data”, ISRO said.

The COP 21 climate conference and the Paris agreement have driven nations to seek international cooperation on climate action. “With this consensus among space agencies from more than 60 nations, including the world’s leading space powers, the international space community and scientists, now have the tools they need to put their talent, intelligence and optimism to work for the good of humankind and our planet,