Historical emissions for the years 1990, 1996, 2000 and 2005 were taken from the latest UNFCCC inventory (UNFCCC, 2014) and converted to AR4 based on a yearly AR4/SAR factor for Costa Rica estimated with gas by gas data from Gieseke & Gütschow (2018). For 2012, we used data from the Third National Communication (Ministerio de Ambiente y Energía, 2014) and the 1st Biennial Update Report (BUR). We interpolated for the years in between. In its Third National Communication and 1st Biennial Update Report, Costa Rica reported its emissions following the IPCC 2006 guidelines, meaning that emissions from Land Use and Forestry are reported as part of the AFOLU (Agriculture, Forestry, and Land Use) category. The CAT analysis requires historical data for LULUCF emissions. We estimated LULUCF emissions for 2010 and 2012 by recalculating the values from the detailed AFOLU sectoral emissions. Updated values for emissions in 2005 and 2010 were provided in the BUR, but because there are no details on the AFOLU sector, we could not use these updated values.
Pledge and NDC
Costa Rica’s NDC states a target to be carbon neutral by 2085 and pledged to keep emissions below 9.37 MtCO2e by 2030, including LULUCF. It is unclear whether the National Decarbonization Plan 2018-2050—announced in February 2019—will replace the NDC’s pledge. As of April 2019, no updated NDC has been submitted to the UNFCCC. Given this unclarity we have not yet excluded the NDC long term target from our assessment. The National Decarbonization plan 2018-2050 presents a pathway to achieve net-zero emissions by 2050 (Gobierno de Costa Rica, 2019b).
Costa Rica’s NDC expresses its 2030 target both as absolute emissions and as ‘25% reduction from 2012 levels’—which according to our estimates is lower than their absolute target. We have therefore estimated a range between 13.7 MtCO2e and 15 MtCO2e in 2030 excl. LULUCF and in GWPs from AR4 based on the two interpretations—the absolute number and the reduction percentage. Our estimations of Costa Rica’s NDC’s long-term target result in a range between 8.9 MtCO2e and 12.3 MtCO2e excluding LULUCF in 2050. We use projections for LULUCF emissions from the 1st Biennial Update Report (Ministerio de Ambiente y Energía, 2015a). These LULUCF projections show a large sink in 2021 and an even larger one in 2030 that previous CAT estimations, meaning that Costa Rica can emit more in other sectors and still achieve its target including LULUCF. In its NDC, Costa Rica also indicates a trajectory to its 2030 target with emissions of 10.9 MtCO2e in 2021 and emissions of 1.2 tCO2e/cap for 2050 and -0.3 tCO2e/cap by 2100, including LULUCF. These targets are presented in global warming potentials from the IPCC’s second assessment report (SAR). The CAT presents all targets excl. LULUCF and global warming potentials (GWPs) from the IPCC’s fourth assessment report (AR4). We have estimated the 2021 target as 13.9 MtCO2e excl. LULUCF in GWPs from AR4.
For the NDC’s 2050 targets we have assumed a range for LULUCF emissions given the absence of national projections. We assume the lower end of LULUCF emissions from 2012—the last historical available year from the BUR—and the higher end as LULUCF emissions from 2030—the last available year from the BUR. We assume these two different ends of the range as the is uncertainty about LULUCF emissions. Efforts—including a REDD+ strategy—exist to reduce emissions in the LULUCF. Nevertheless, a national study (Sancho, Rivera and Obando, 2015), which estimates emissions from LULUCF sector by examining the forest compositions and historical trends, projects that the LULUCF sink will start to shrink after 2029 and emissions from this sector will become positive in 2050.
Current policy projections
Our current policy projections are based on the Conservative baseline scenario from the 1st Biennial Update Report (BUR) (Ministerio de Ambiente y Energía, 2015a) and national estimations of Law 9518 from 2018 (Gobierno de Costa Rica, MINAE and MOPT, 2019). The conservative baseline scenario from the first BUR includes only actions or projects at a sector or economy wide level that are already implemented or which have received a first investment that makes them irreversible (Ministerio de Ambiente y Energía, 2015a).
Planned policy projections
We have included a planned policy pathway, which is line with the 1.5 pathway of Costa Rica’s Decarbonisation Plan 2018-2050 (Gobierno de Costa Rica, 2019b). Since the pathway starts only in 2018, and given that inventory data is only available until 2012, we have harmonized to current policy projections between 2012 and 2018. We have added a range for planned policy projections until 2030. The upper end of the range is a pathway assuming implementation of policies for the energy sector only, whereas the lower end of the range assumes implementation of policies from the energy, industry, agriculture and waste sectors.
Global Warming Potentials
The CAT uses Global Warming Potential (GWP) values from the IPCC's Fourth Assessment Report (AR4) for all its figures and time series. Assessments completed prior to December 2018 (COP24) used GWP values from the Second Assessment Report (SAR).