Buttons are hooked into the system timer in their constructor for regular debouncing. However, if you want to completely remove this feature and use the physical pins for other purposes, you can delete uBit. It is then possible to use a MicroBitPin instance around the physical pin name to control it directly without interference from the DAL. These pins are allocated to the I2C bus, which is used by both the on-board motion sensor.
It is strongly suggested that you avoid using these pins for any function other than I2C. It is possible to disable the DAL services that use these pins as the I2C bus, but the motion sensor device will still be connected to the bus, and may try to interpret the signals as data payloads, which could create some undesirable side effects on the SDA and interrupt pins.
There are 4K7 pull-ups fitted to both pins on the board, so the best use for these two signals is to add other I2C devices. The main reason you might choose to use these pins for other purposes would be if you were designing your own micro:bit variant without any I2C devices, and then it would free up two more pins for other purposes. There is a dedicated page on power supply capabilities and parameters , which better defines how you can use the GND and 3V rings. NOTE 2: A common way that the maximum pin voltages can be exceeded, is to attach an inductive load such as a speaker, motor, or piezo sounder directly to the pin.
It can be integrated with your application by setting a few. Active Query Builder is a. Net-ready ActiveX visual query builder component which gives your end-users the ability to create complex SQL queries containing unions and sub-queries via an intuitive visual interface.
It has complete support of Oracle,. Active Shield is an ultimate heuristic screen against trojans, spyware and adware. Don't wait while malicious programs strike roots in your computer.
Don't let them ever reach you PC! Remember that active defense is more effective than passive. Identify, move and disable inactive users in your Active Directory Domain. All domain controllers are scanned for the lastLogon data, so you you can be sure the days of inactivity are accurate. Users that have never logged on are also indentified. Journal of Traumatic Stress , May 28, Clinical trials of COVID vaccines mostly excluded patients taking immunosuppressive medication, which keep the immune system in check.
The researchers studied outcomes for nearly 15, patients taking medication for inflammatory bowel disease. Unvaccinated patients in this population had a much higher rate of COVID infection than vaccinated patients.
Partial vaccination did not significantly reduce the hazard of infection. The results could help increase patient and provider willingness to vaccinate immunosuppressed patients, say the researchers. Gastroenterology , May 25, Researchers surveyed nearly 3, Veterans receiving treatment for depression in VA. They found that almost all patients screened positive for at least one other mental health condition.
About half had four or more conditions. Results showed that depression severity plays a large role in impairment caused by other mental health conditions. The findings suggest that addressing depression could help improve symptoms of other mental health conditions, say the researchers. Journal of Affective Disorders , April 27, While some Veterans receive health care through VA, many get their health coverage outside the system.
Researchers looked at health care costs for more than 13, Veterans receiving health care outside VA before and after the Affordable Care Act was passed. Veterans 65 and older did not see a similar reduction in catastrophic health care costs.
Journal of General Internal Medicine , May 6, Levels of IgM, short-term antibodies that protect from initial infection, peak at about 20 days after infection and then decline. IgG—longer-term antibodies—levels peak about 25 days after symptom onset and remain detectable for at least days.
Some evidence suggests that older age, greater COVID severity, and presence of symptoms may be linked to higher antibody levels. Some adults do not develop antibodies for unclear reasons. Annals of Internal Medicine , March 16, They found that a subgroup of patients with specific brain connectivity traits were more likely than others to benefit from prolonged exposure therapy.
They did not find any brain connectivity patterns related to alcohol consumption. The results could lead to treatments that target brain connectivity to boost treatment effectiveness, say the researchers. Psychological Medicine , April 30, In , the Veterans Choice Act made it possible for some VA patients to receive health care in the community instead of from VA facilities. Researchers looked at data from over 3, counties across the country.
Rural counties saw the greatest increase in community care use. Counties with a VA facility were less likely to see community care increases. The results suggest that community care may enhance primary care access for Veterans in areas farther away from VA facilities, according to the researchers.
Medical Care , June 1, The PTSD group reported smaller social networks and greater loneliness. The researchers used magnetic resonance imaging MRI while participants performed a memory task involving social relationships.
Imaging of the PTSD group during the memory task showed hyperactivation of the default network, the connection between different parts of the brain. The results suggest that poor social connection in people with PTSD could be caused by disrupted brain connectivity, according to the researchers. Depression and Anxiety , Feb. Cognitive behavioral therapy aims to improve mental distress by helping a person modify and control their thought processes. Researchers reviewed the available evidence on this approach for people with mild cognitive impairment and dementia.
Multiple studies showed that cognitive behavioral therapy can improve anxiety, depression, and quality of life in these patients.
Some evidence also suggests that the therapy can reduce insomnia and improve sleep quality. The results show a need for more study on cognitive behavioral therapy in dementia patients, especially with regard to insomnia, say the researchers.
In peripheral artery disease, narrowed arteries reduce blood flow to the limbs. Researchers looked at genome-wide study data on blood pressure and cardiovascular disease.
They found that higher pulse pressure and mean arterial pressure directly increase the risk of peripheral artery disease. Use of blood pressure medications such as beta-blockers and diuretics was linked to lower risk of peripheral artery disease.
This suggests that medications that lower blood pressure protect against the disease. More research is needed to clarify how exactly blood pressure influences peripheral artery disease, say the researchers. Arteriosclerosis, Thrombosis, and Vascular Biology , April 15, In TMS, magnetic pulses are applied to the outside of the head to influence the electrical signals in the brain. It has been shown to help with both PTSD and major depressive disorder.
The treatments are similar but use different frequencies and duration. Both methods were safe and reduced PTSD and depression symptoms. However, Veterans who received iTMS reported poorer outcomes.
The results could help clinicians choose the best form of TMS for their patients, say the researchers. Journal of Traumatic Stress , May 11, At nine and 11 months after treatment, hippocampus-related learning and memory were preserved.
Important membrane structures and receptors also remained intact in the treated mice, while control mice had damage. Molecular Therapy , March 29, Cannabis use disorder refers to addiction to the substance and negative social impacts of excessive use. Evidence suggests that some Veterans attempt to self-medicate with cannabis for conditions such as PTSD. They found that cannabis use disorder was associated with increased odds of difficulty managing anger, aggressive impulses, and problems controlling violence.
The study could not determine whether cannabis use disorder causes aggression, or whether people with more aggressive tendencies were more likely to develop the disorder. The results show a need to assess violent tendencies along with cannabis use disorder, say the researchers. Journal of Psychiatric Research , April 22, Researchers analyzed data on social functioning for more than 1, Veterans. Veterans with both conditions were more likely to report worse social well-being, compared to those with only PTSD, only SUD, or neither disorder.
Veterans with both conditions were also more likely to have worse job and financial well-being. Psychological Trauma , March 4, The study assessed how 50 patients recovering from stroke did on two arm movement tasks.
Patients performed worse on the more cognitively demanding task, especially immediately after their strokes. Poorer performance on the more complex test was linked to broad injury beyond the parts of the brain involved with movement, while performance on the simpler task was mostly linked to injury of the brain regions related to motor function.
The results show that motor ability and cognitive function must be considered together when treating stroke patients, say the researchers. Neurology , April 15, Researchers surveyed Veterans with colorectal cancer. Their distance from a VA facility was not strongly linked to transportation difficulty.
Rather, a chaotic lifestyle was the largest cause of transportation barriers. Chaotic lifestyle mainly means that patients have an unpredictable schedule. Identifying Veterans with chaotic lifestyles could allow for timely intervention to improve their cancer care, say the researchers. The researchers looked at outcomes on more than 73, VA patients who survived COVID and close to 5 million who did not contract the disease.
People who have recovered from COVID also are at increased risk of health problems affecting virtually every organ system in the body, not just the lungs.
Nature , April 22, Researchers analyzed the cerebrospinal fluid and performed cognitive testing on 81 cognitively normal older adults and with mild cognitive impairment. Higher levels of tau protein were associated with poorer memory performance in the cognitive impairment group only.
The study looked at more than Veterans with at least one mental health disorder. Forty-eight percent had a diagnosis of non-suicidal self-injury disorder. Those with non-suicidal self-injury disorder were nearly five times more likely to have a suicide attempt than those without.
The results show that understanding the link between self-injury and suicide could improve prevention, say the researchers.
Journal of Affective Disorders , March 15, The study followed patients during the last few days of their stay at a skilled nursing facility and a few days after discharge. The number of steps taken per day was very low and did not increase much when patients returned home. Patients thought that they were more physically active than they actually were. The results highlight the need to encourage physical activity both in and out of skilled nursing facilities, say the researchers.
Disability and Rehabilitation , April 9, Researchers looked at data from two large national surveys. Suicide prevention efforts in collaboration with these communities are needed, conclude the researchers. Military Psychology , April 8, More than half of Veterans who die by suicide visit their primary care provider a month before their death. All participants received health care through VA.
The majority felt that discussing firearms safety was acceptable and needed, even if discussions were uncomfortable. They cited the urgent need to prevent Veteran suicide for this feeling. The findings show that a Veteran-focused approach to firearms safety could help address Veteran suicide, say the researchers.
Researchers assessed more than Veterans twice during a three-year period. They found that trauma exposure directly predicted diet quality. The findings suggest that consuming unhealthy food was driven by emotional suppression.
The researchers did not find any link between PTSD symptoms and amount of exercise. The results could help treat medical comorbidities in patients with PTSD, say the researchers. European Journal of Psychotraumatology , March Forty Veterans diagnosed with nonsuicidal self-injury disorder completed an electronic diary for 28 days.
The most common type of self-injury was punching walls or objects. Momentary feelings of anger or hostility were linked to subsequent self-injury urges. The reverse was not true: self-injury did not lead to feelings of anger. The results highlight the need to assess and treat patients who self-injure for anger issues, say the researchers. Journal of Psychiatric Research , March Ischemia is when an organ does not get enough blood, which can cause serious organ problems.
Researchers treated ischemic mice with smooth muscle cells derived from pluripotent stem cells that had been grown in a lab. Pluripotent stem cells are base cells that can be reprogramed to form into different types of body cells. Treated mice had improved functional outcomes and blood flow, compared with controls.
They also showed signs of improved wound healing. The results show that stem-cell therapy has potential to effectively treat ischemia in humans, say the researchers. Cells , April 2, The nine-week program used peer support to improve patient engagement and health by teaching whole health concepts and strategies.
Participants had a significant decrease in perceived stress. They also showed significant improvements in mental health and quality of life.
Patients were more engaged with their health care after the program. The findings suggest that using peers to guide patients in exploring their values and goals can improve their health and engagement, say the researchers. They then used machine learning to look for these features in more than 9, medical notes.
Notes written about Black patients were more likely to contain all three signs of disbelief, compared with notes on white patients. Notes about female patients were more likely than male patient notes to contain quotes.
The results suggest that Black patients are less likely to be believed when they describe their symptoms or experiences, say the researchers. Journal of General Internal Medicine , March 22, Nurses identified several logistical problems that made providing care over video more difficult. They noted the complexity of scheduling appointments, local barriers to care, and difficulty of remotely managing acutely ill patients.
The nurses surveyed also said that it is harder to gather sensory data during remote visits. Video makes it harder to build provider-patient relationships, as well. Patients were aware of the limitations on physical exams but not the logistical challenges. Training videos and mentoring on best practices could improve the telehealth experience, according to the researchers.
Journal of Nurse Practitioners , March 20, A region of the kidney called the proximal tubule helps control the acid-base balance in the blood. Acidosis is when acids are not properly removed from the blood into the urine by the proximal tubule.
In addition to causing problems with the blood, acidosis causes the urine to become more alkaline. The researchers used a mouse model of this condition to study how this shift may lead to kidney stones. They found that the shift in urine pH causes a build-up of calcium ions, which may form into stones.
Dysregulation of the proximal tubule can also cause cell damage, which further leads to stone formation when damaged cellular fragments bind with calcium crystals. The results improve the understanding of the biological processes behind kidney stones, say the researchers. International Journal of Molecular Sciences , March 17, Researchers assessed more than 1, former and current military personnel with a history of combat exposure.
Eighty-two percent had a history of mild TBI. The results suggest that TBI and PTSD should be evaluated and treated together in Veterans and service members who experienced combat, say the researchers.
Journal of Head Trauma Rehabilitation , Feb. Diabetes can increase the risk of serious heart problems, largely through increased obesity risk. Opioids are known to aid in cardiac stress tolerance, but diabetes disrupts how the body responds to opioids. The researchers tested a five-day, high-dose morphine treatment in a mouse model of type 2 diabetes. The treatment improved blood pressure stability, reversed cardiac depression, and improved heart function. It also restored impaired molecular heart processes.
The findings suggest that short-term, high-dose morphine could help diabetic patients recover from acute cardiovascular events, say the researchers. The researchers analyzed brain scans of nearly 1, patients who were dependent on alcohol, nicotine, cocaine, methamphetamine, or cannabis. They compared them to scans of almost 1, patients without substance dependence. The results showed that addiction was significantly linked to asymmetry of the nucleus accumbens, a region in the lower middle of the brain.
The right side of the nucleus accumbens was smaller in patients with substance dependence. This effect was largest in patients with alcohol and nicotine dependence. More research is needed on whether substance use causes the brain asymmetry, or whether the asymmetry increases the risk of addiction, according to the researchers.
Addiction Biology , Jan. Researchers looked at COVID infection data for nearly , students and more than 99, staff attending in-person schools in the Massachusetts public school system. They found that the infection rate was similar in districts with policies requiring three feet of physical distance, compared with districts requiring six feet.
Increasing physical distance may not be necessary to prevent COVID cases in schools, concluded the researchers, provided that universal mask mandates and other precautions are implemented. Clinical Infectious Diseases , March 10, Moral injury experienced during deployment includes perpetrating, failing to prevent, witnessing, or learning about acts that transgress deeply held moral beliefs.
Reports of transgressions by others and feelings of betrayal were more common than personal transgressions. These experiences were linked with a higher risk of suicidal thoughts, making a suicide plan, and suicide attempts. While the effect of moral injury on suicidal behavior was significant, PTSD and depression had greater effects on suicide risk.
The results show that more work to evaluate and address moral injury in Veterans is needed, say the researchers.
Depression and Anxiety , March 5, The researchers looked at data on screening exams at VA facilities and partner sites over a six-year period. They found that screening numbers varied by more than fold across different regions.
Screenings were particularly low in more rural locations. Nine of the 12 states with the highest proportions of rural Veterans had three or fewer lung cancer screening facilities. The findings indicate that VA needs to make efforts to provide more equitable access to lung cancer screening, according to the researchers.
Chest , Feb. Nurses often experience high levels of stress and burnout, which has been exacerbated by the COVID pandemic. Registered nurses working in VA acute care units participated in an online mantram repetition program to learn stress coping skills. Nurses who participated in the program reported increased mindfulness, spiritual well-being, and presence while with patients. They also experienced less burnout. Patients being treated by participating nurses noticed greater levels of presence from nurses and were highly satisfied with their care.
The results suggest that portable stress reduction techniques can help alleviate nursing burnout, say the researchers. Nursing Outlook , Feb.
The study included data from nearly , Veterans over a year period. Sleep disorders seen in this population included sleep apnea, insomnia, excessive sleepiness during the day, and sleep-related movement disorders. The findings show that better prevention and long-term management for sleep are needed for Veterans with TBI, say the researchers.
Neurology , March 3, The locus coeruleus is a structure in the brainstem involved in the sleep-wake cycle and in cognitive function. Researchers assessed cognitive function and MRI scans in nearly older Veterans. They found that reduced locus coeruleus integrity was linked to sleep dysfunction, poorer memory, and greater odds of mild cognitive impairment. Losing height is common in older adults as age-related changes in the bones, muscles, and joints occur.
The researchers studied a sample of nearly 3, older men. They found that men who had lost at least three centimeters in height over a period of seven years had nearly double the risk of a hip fracture, compared with those who lost less than a centimeter in height. Men who lost at least three centimeters had an Those losing less than a centimeter had a 2.
The risk of other bone fractures was also higher in men who had lost height. The results suggest that height loss should be considered when assessing fracture risk, say the researchers. Review quick start guide. The migration is easy and largely push-button, and requires minimal to no changes in existing scripts. Watch this video for a quick demo of migration. Contact information is available on the Siemens EDA website. We facilitate access to original data with the understanding that primary data sets will be referenced in future work see Table 2 for how to cite the data sets.
Descriptions of the measurements, models, and methodologies follow below and detailed descriptions of each component are provided elsewhere. Table 2 How to cite the individual components of the global carbon budget presented here.
This is the 15th version of the global carbon budget and the ninth revised version in the format of a living data update in Earth System Science Data. It builds on the latest published global carbon budget of Friedlingstein et al.
The main changes are 1 the inclusion of data of the year and a projection for the global carbon budget for year ; 2 the inclusion of gross carbon fluxes associated with land-use changes; and 3 the inclusion of cement carbonation in the fossil fuel and cement component of the budget E FOS. The main methodological differences between recent annual carbon budgets — are summarized in Table 3 and previous changes since are provided in Table A7. Table 3 Main methodological changes in the global carbon budget since Methodological changes introduced in one year are kept for the following years unless noted.
Empty cells mean there were no methodological changes introduced that year. Table A7 lists methodological changes from the first global carbon budget publication up to The estimates of global and national fossil CO 2 emissions E FOS include the combustion of fossil fuels through a wide range of activities e. The estimates of E FOS in this study rely primarily on energy consumption data, specifically data on hydrocarbon fuels, collated and archived by several organizations Andres et al.
We use four main data sets for historical emissions — :. We assess these to be the most accurate estimates because they are compiled by experts within countries that have access to the most detailed data, and they are periodically reviewed. Global and national cement emissions updated from Andrew to include the latest estimates of cement production and clinker ratios.
In the following section we provide more details for each data set and describe the additional modifications that are required to make the data set consistent and usable. Fuel masses and volumes are converted to fuel energy content using country-level coefficients provided by the UN and then converted to CO 2 emissions using conversion factors that take into account the relationship between carbon content and energy heat content of the different fuel types coal, oil, natural gas, natural gas flaring and the combustion efficiency Marland and Rotty, ; Andrew, a.
Specific country updates. For India, the data reported by CDIAC are for the fiscal year running from April to March Andrew, a , and various interannual variations in emissions are not supported by official data. Given that India is the world's third-largest emitter and that a new data source is available that resolves these issues, we replace CDIAC estimates with calendar-year estimates through by Andrew b. For Norway, CDIAC's method of apparent energy consumption results in large errors, and we therefore overwrite emissions before with estimates derived from official Norwegian statistics.
We apply the BP growth rates by fuel type coal, oil, natural gas to estimate emissions based on estimates UNFCCC Annex I countries , and to estimate — emissions based on estimates remaining countries except India.
For the most recent years, natural gas flaring is assumed to be constant from the most recent available year of data for Annex I countries, for the remainder. We apply two exceptions to this update using BP data. The first is for China's coal emissions, for which we use growth rates reported in official preliminary statistics for NBS, b. Estimates of emissions from cement production are updated from Andrew Other carbonate decomposition processes are not included explicitly here, except in national inventories provided by Annex I countries, but are discussed in Sect.
Country mappings. We reduce the list to countries by reallocating emissions to currently defined territories, using mass-preserving aggregation or disaggregation. Examples of aggregation include merging East and West Germany to the currently defined Germany. Examples of disaggregation include reallocating the emissions from the former USSR to the resulting independent countries. For disaggregation, we use the emission shares when the current territories first appeared e.
USSR in , and thus historical estimates of disaggregated countries should be treated with extreme care. In addition, we aggregate some overseas territories e. Global total. The global estimate is the sum of the individual countries' emissions and international aviation and marine bunkers. The CDIAC global total differs from the sum of the countries and bunkers since 1 the sum of imports in all countries is not equal to the sum of exports because of reporting inconsistencies, 2 changes in stocks, and 3 the share of non-oxidized carbon e.
From the edition CDIAC now includes changes in stocks in the global total Dennis Gilfillan, personal communication, , removing one contribution to this discrepancy. To remove this discrepancy we now calculate the global total as the sum of the countries and international bunkers. Cement carbonation. We estimate this CO 2 sink as the average of two studies in the literature Cao et al.
Both studies use the same model, developed by Xi et al. The trends of the two studies are very similar. Modelling cement carbonation requires estimation of a large number of parameters, including the different types of cement material in different countries, the lifetime of the structures before demolition, of cement waste after demolition, and the volumetric properties of structures, among others Xi et al.
Lifetime is an important parameter because demolition results in the exposure of new surfaces to the carbonation process. The most significant reasons for differences between the two studies appear to be the assumed lifetimes of cement structures and the geographic resolution, but the uncertainty bounds of the two studies overlap.
In the present budget, we include the cement carbonation carbon sink in the fossil CO 2 emission component E FOS , unless explicitly stated otherwise. This includes an assessment of uncertainties in the amounts of fuel consumed, the carbon and heat contents of fuels, and the combustion efficiency.
Uncertainties of emissions are likely to be mainly systematic errors related to underlying biases of energy statistics and to the accounting method used by each country. Consumption-based emission attribution results e. Davis and Caldeira, provide additional information to territorial-based emissions that can be used to understand emission drivers Hertwich and Peters, and quantify emission transfers by the trade of products between countries Peters et al. The consumption-based emissions have the same global total but reflect the trade-driven movement of emissions across the Earth's surface in response to human activities.
We estimate consumption-based emissions from — by enumerating the global supply chain using a global model of the economic relationships between economic sectors within and between every country Andrew and Peters, ; Peters et al.
We estimate the sector-level CO 2 emissions using the GTAP data and methodology, include flaring and cement emissions from CDIAC, and then scale the national totals excluding bunker fuels to match the emission estimates from the carbon budget. We do not provide a separate uncertainty estimate for the consumption-based emissions, but based on model comparisons and sensitivity analysis, they are unlikely to be significantly different than for the territorial emission estimates Peters et al.
We apply a leap-year adjustment where relevant to ensure valid interpretations of annual growth rates. This affects the growth rate by about 0. The relative growth rate of E FOS over time periods of greater than 1 year can be rewritten using its logarithm equivalent as follows:. Here we calculate relative growth rates in emissions for multi-year periods e.
Our analysis this year is different to previous editions of the Global Carbon Budget, as there have been several independent studies estimating global CO 2 emissions in response to restrictions related to the COVID pandemic, and the highly unusual nature of the year makes the projection much more difficult.
We separate each method into two parts: first we estimate emissions for the year to date YTD and, second, we project emissions for the rest of the year Each method is presented in the order it was published. Here we use an update through to 13 November. The parameters for the changes in activity by sector were updated for the industry and aviation sectors, to account for the slow recovery in these sectors observed since the first peak of the pandemic.
Specific country-based parameters were used for India and the USA, which improved the match to the observed monthly emissions from Sect.
By design, this estimate does not include the background seasonal variability in emissions e. To account for the seasonality in emissions where data are available, the mean seasonal variability over — was calculated from available monthly emissions data for the USA, EU27, and India data from Sect. The uncertainty provided reflects the uncertainty in activity parameters.
A projection is used to fill the data from 14 November to the end of December, assuming countries where confinement measures were at level 1 targeted measures on 13 November remain at that level until the end of Forster et al.
The mobility data were used to estimate daily fractional changes in emissions from power, surface transport, industry, residential, and public and commercial sectors.
We use an updated version of Forster et al. Liu et al. We use an updated version of Liu et al. For purposes of comparison with other methods, we use a simple approach to extrapolating their observations by assuming the remaining months of the year change by the same relative amount compared to in the final month of observations.
Previous editions of the Global Carbon Budget GCB have estimated YTD emissions and performed projections, using sub-annual energy consumption data from a variety of sources depending on the country or region. The YTD estimates have then been projected to the full year using specific methods for each country or region. This year we make some adjustments to this approach, as described below, with detailed descriptions provided in Appendix C. The YTD estimate is based on monthly data from China's National Bureau of Statistics and Customs, with the projection based on the relationship between previous monthly data and full-year data to extend the monthly data to estimate full-year emissions.
The YTD estimates are based on monthly consumption data of coal, oil, and gas converted to CO 2 and scaled to match the previous year's emissions. We use the same method for the EU27 as for Carbon Monitor described above to generate a full-year projection. YTD estimates are updated from Andrew b , which calculates monthly emissions directly from detailed energy and cement production data. We use the same method for India as for Carbon Monitor, described above, to generate a full-year projection.
Rest of the world. There is no YTD estimate, while the projection is based on a GDP estimate from the IMF combined with average improvements in carbon intensity observed in the last 10 years, as in previous editions of the Global Carbon Budget e. Friedlingstein et al. In the results section we present the estimates from the four different methods, showing the YTD estimates to the last common historical data point in each data set and the projections for The net CO 2 flux from land use, land-use change, and forestry E LUC , called land-use change emissions in the rest of the text includes CO 2 fluxes from deforestation, afforestation, logging and forest degradation including harvest activity , shifting cultivation cycle of cutting forest for agriculture, then abandoning , and regrowth of forests following wood harvest or abandonment of agriculture.
Emissions from peat burning and drainage are added from external data sets see Sect. Only some land-management activities are included in our land-use change emissions estimates Table A1. Some of these activities lead to emissions of CO 2 to the atmosphere, while others lead to CO 2 sinks.
E LUC is the net sum of emissions and removals due to all anthropogenic activities considered. Our annual estimate for — is provided as the average of results from three bookkeeping approaches Sect. All three data sets are then extrapolated to provide a projection for Sect. Table 4 References for the process models, p CO 2 -based ocean flux products, and atmospheric inversions included in Figs. All models and products are updated with new data to the end of the year , and the atmospheric forcing for the DGVMs has been updated as described in Sect.
See also Best et al. Download XLSX. Land-use change CO 2 emissions and uptake fluxes are calculated by three bookkeeping models. These are based on the original bookkeeping approach of Houghton that keeps track of the carbon stored in vegetation and soils before and after a land-use change transitions between various natural vegetation types, croplands, and pastures.
Literature-based response curves describe decay of vegetation and soil carbon, including transfer to product pools of different lifetimes, as well as carbon uptake due to regrowth. In addition, the bookkeeping models represent long-term degradation of primary forest as lowered standing vegetation and soil carbon stocks in secondary forests and also include forest management practices such as wood harvests. BLUE and HandN exclude land ecosystems' transient response to changes in climate, atmospheric CO 2 , and other environmental factors and base the carbon densities on contemporary data from literature and inventory data.
Since carbon densities thus remain fixed over time, the additional sink capacity that ecosystems provide in response to CO 2 fertilization and some other environmental changes is not captured by these models Pongratz et al. On the contrary, OSCAR includes this transient response, and it follows a theoretical framework Gasser and Ciais, that allows separate bookkeeping of land-use emissions and the loss of additional sink capacity.
Only the former is included here, while the latter is discussed in Sect. A notable change of HandN over the original approach by Houghton used in earlier budget estimates is that no shifting cultivation or other back and forth transitions at a level below country are included.
Only a decline in forest area in a country as indicated by the Forest Resource Assessment of the FAO that exceeds the expansion of agricultural area as indicated by FAO is assumed to represent a concurrent expansion and abandonment of cropland.
We linearly increase tropical drainage emissions from 0 in , consistent with HandN's assumption, and keep emissions from the often old drained areas of the extra-tropics constant pre This adds 8. Peat fires add another 2.
The three bookkeeping estimates used in this study differ with respect to the land-use change data used to drive the models. HandN base their estimates directly on the Forest Resource Assessment of the FAO, which provides statistics on forest-area change and management at intervals of 5 years currently updated until FAO, The data are based on country reporting to FAO and may include remote-sensing information in more recent assessments.
To constrain the models' interpretation of whether rangeland implies the original natural vegetation to be transformed to grassland or not e. This is implemented in BLUE.
HandN was extended here for to by adding the annual change in total tropical emissions to the HandN estimate for , including estimates of peat drainage and peat burning as described above as well as emissions from tropical deforestation and degradation fires from GFED4. Gross fluxes for HandN and OSCAR were extended to based on a regression of gross sources including peat emissions to net emissions for recent years.
BLUE's value was adjusted because the LUH2-GCB forcing for was an extrapolation of earlier years, thus not capturing the rising deforestation rates occurring in South America in and the anomalous fire season in equatorial Asia see Sects.
Anomalies of GFED tropical deforestation and degradation and equatorial Asia peat fire emissions relative to are therefore added. Resulting dynamics in the Amazon are consistent with BLUE simulations using directly observed forest cover loss and forest alert data Hansen et al. For the first time we provide estimates of the gross land-use change fluxes from which the reported net land-use change flux, E LUC , is derived as a sum.
Gross fluxes are derived internally by the three bookkeeping models: gross emissions stem from decaying material left dead on site and from products after clearing of natural vegetation for agricultural purposes, wood harvesting, emissions from peat drainage and peat burning, and, for BLUE, additionally from degradation from primary to secondary land through usage of natural vegetation as rangeland.
Gross removals stem from regrowth after agricultural abandonment and wood harvesting. The DGVMs account for deforestation and regrowth, the most important components of E LUC , but they do not represent all processes resulting directly from human activities on land Table A1. All DGVMs represent processes of vegetation growth and mortality, as well as decomposition of dead organic matter associated with natural cycles, and include the vegetation and soil carbon response to increasing atmospheric CO 2 concentration and to climate variability and change.
Some models explicitly simulate the coupling of carbon and nitrogen cycles and account for atmospheric N deposition and N fertilizers Table A1. The DGVMs are independent from the other budget terms except for their use of atmospheric CO 2 concentration to calculate the fertilization effect of CO 2 on plant photosynthesis. The data are based on the available annual FAO statistics of change in agricultural land area available until HYDE version 3.
HYDE forcing was also corrected for Brazil for the years — After the year HYDE extrapolates cropland, pasture, and urban land-use data until the year This new data set is of quarter-degree fractional areas of land-use states and all transitions between those states, including a new wood harvest reconstruction and new representation of shifting cultivation, crop rotations, and management information including irrigation and fertilizer application. The land-use states include five different crop types in addition to the pasture—rangeland split discussed before.
Wood harvest patterns are constrained with Landsat-based tree cover loss data Hansen et al. DGVMs implement land-use change differently e. Similarly, model-specific assumptions are applied to convert deforested biomass or deforested areas and other forest product pools into carbon, and different choices are made regarding the allocation of rangelands as natural vegetation or pastures.
The forcing data also include global atmospheric CO 2 , which changes over time Dlugokencky and Tans, , and gridded, time-dependent N deposition and N fertilizers as used in some models; Table A1. Two sets of simulations were performed with each of the DGVMs. Both applied historical changes in climate, atmospheric CO 2 concentration, and N inputs. The two sets of simulations differ, however, with respect to land use: one set applies historical changes in land use, the other a time-invariant pre-industrial land cover distribution and pre-industrial wood harvest rates.
By difference of the two simulations, the dynamic evolution of vegetation biomass and soil carbon pools in response to land-use change can be quantified in each model E LUC. Differences between the bookkeeping models and DGVM models originate from three main sources: the different methodologies, which among other things lead to inclusion of the loss of additional sink capacity in DGVMs Sect. We examine the results from the DGVM models and of the bookkeeping method and use the resulting variations as a way to characterize the uncertainty in E LUC.
However there are large differences among individual DGVMs standard deviation at around 0. We assign low confidence to the annual estimates of E LUC because of the inconsistencies among estimates and of the difficulties in quantifying some of the processes in DGVMs.
Table 5 Comparison of results from the bookkeeping method and budget residuals with results from the DGVMs and inverse estimates for different periods, the last decade, and the last year available. All values are rounded to the nearest 0. The ranges given include varying numbers in parentheses of inversions in each decade Table A4. We project the land-use emissions for BLUE, HandN, and OSCAR, starting from their estimates for assuming unaltered peat drainage, which has low interannual variability, and the highly variable emissions from peat fires, tropical deforestation, and degradation as estimated using active fire data MCD14ML; Giglio et al.
During most years, emissions during January-September cover most of the fire season in the Amazon and Southeast Asia, where a large part of the global deforestation takes place and our estimates capture emissions until 31 October. By contrast, fire emissions in South America remained above-average in , with the slight decrease since estimated in GFED4. This is consistent with slightly reduced deforestation rates in compared to note that often Amazon deforestation is reported from August of the previous to July of the current year; for such reporting, deforestation will tend to be higher in than in by including strong deforestation August—December Overall, however, we have low confidence in our projection due to the large uncertainty range we associate with past E LUC , the dependence of emissions on legacy fluxes from previous years, uncertainties related to fire emissions estimates, and the lack of data before the end of the year that would allow deforested areas to be quantified accurately.
Also, an incomplete coverage of degradation by fire data makes our estimates conservative, considering that degradation rates in the Amazon increased from to INPE, For the — period, the global growth rate is based on measurements of atmospheric CO 2 concentration averaged from the Mauna Loa and South Pole stations, as observed by the CO 2 Program at Scripps Institution of Oceanography Keeling et al.
For the — time period, the global growth rate is based on the average of multiple stations selected from the marine boundary layer sites with well-mixed background air Ballantyne et al. The annual growth rate is estimated by Dlugokencky and Tans from atmospheric CO 2 concentration by taking the average of the most recent December—January months corrected for the average seasonal cycle and subtracting this same average 1 year earlier.
The uncertainty around the atmospheric growth rate is due to four main factors: first, the long-term reproducibility of reference gas standards around 0.
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