Bottom-up Climate Finance Needs
Since 2021, CPI has worked to support a collective understanding of the climate finance needed to reach net zero carbon emissions by 2050. Accurately assessing the size of the global climate finance gap can enable decision-makers to mobilize finance effectively, quickly, and to where it is most needed. While top-down modelling gives a comprehensive view of global finance needs to align to a 1.5oC pathway, needs estimates can also be developed at the country level, based on national priorities.
Referred to as bottom-up needs, this country-level approach is critical for understanding nations’ climate finance ambitions and required level of international support to reach their mitigation and adaptation objectives. Bottom-up needs outline domestic (unconditional) and international (conditional) capital required to achieve national climate goals, as stated in official documents such as Nationally Determined Contributions (NDCs) and National Adaptation Plans (NAPs).
CPI’s bottom-up climate finance needs are derived from the collection and standardization of climate finance needs data from 169 NDCs and provide a comprehensive overview of climate finance needs as presented by countries. Though NDCs remain the primary source of CPI’s bottom-up needs, CPI’s newly updated data also compiles adaptation finance needs from over 90 National Adaptation Plans (NAPs) as a supplementary source. Alongside our assessment of top-down needs and our wider tracking and analysis of climate finance flows, this analysis can help identify the largest climate finance gaps at the country level, track progress against climate targets, and better inform decision-makers and financial institutions on how to increase the speed, scale, and quality of climate finance in alignment with countries’ sectoral priorities.
To explore the data on bottom-up needs in more detail, visit our bottom-up needs interactive dashboard.
Climate finance needs in Nationally Determined Contributions (NDCs)
HOW MUCH DO COUNTRIES NEED TO ACHIEVE THEIR NDC GOALS?
Of the 194 UNFCCC parties that have ratified the Paris Agreement and subsequently submitted NDCs, 123 include explicit estimates of finance needed in their NDCs.
Our updated compilation of bottom-up needs shows that for these 123 parties, a cumulative investment of USD 5.7 trillion is required from 2025-2035 to meet their climate goals. Of the total estimated needs for 2025-2035, 74% (USD 4.2 trillion) will be required for mitigation and 20% (USD 1.2 trillion) for adaptation and resilience. The remaining 6% (USD 347 billion) will be needed for cross-cutting initiatives that target both mitigation and adaptation objectives (dual benefits). It should be noted that bottom-up needs are dwarfed by those estimated using global, 1.5°C-aligned models (top-down needs).
WHERE SHOULD FINANCE BE DIRECTED?
Bottom-up needs estimated in NDCs are largely concentrated in emerging markets and developing economies (EMDEs), reflecting both the higher climate vulnerability of these regions, as well as the nature of the Paris Agreement, which encourages non-Annex I countries to indicate the level of international support they require to meet their NDC targets. More than 80% of recorded bottom-up needs (USD 4.7 trillion) are concentrated in EMDEs.
Notably, sub-Saharan Africa has the largest reported bottom-up needs, accounting for 29% (USD 1.7 trillion) of total needs from 2025-2035. East Asia and the Pacific and South Asia also have a significant share of total bottom-up needs, each requiring nearly USD 1 trillion between 2025-2035.These regions are some of the most vulnerable to climate change, despite their minimal contributions to historical global GHG emissions.
However, it should be noted that regional comparison of bottom-up needs is partly limited by data availability, as not all countries cost their finance needs in their NDCs.
WHAT LEVEL OF INTERNATIONAL SUPPORT WILL BE NEEDED IN EMDEs?
Many EMDEs will require significant international support to meet their stated climate objectives, known as conditional climate finance needs. For EMDEs, 32% of stated climate finance needs in NDCs are conditional on international support, and just 12% are unconditional, or expected to come from domestic public sources. For the remaining 56% of needs for EMDEs, the NDCs did not specify if the finance would be provided domestically or obtained externally. However, given the scale of climate finance needs compared to limited domestic resources in many countries, it is highly likely that significant international support will be required.
The figure below highlights the portion of stated needs that are contingent on international support across regions
“Unspecified” here refers to needs that were not classified as unconditional in the NDC
Climate finance needs in National Adaptation Plans (NAPs)
WHERE DO NATIONAL ADAPTATION PLANS FIT IN?
For the first time, CPI’s bottom-up needs database also includes adaptation finance needs from National Adaptation Plans (NAPs), the national planning instruments countries use to identify medium- and long-term adaptation needs. Of the 91 NAPs reviewed, 58 quantify adaptation finance needs, totalling USD 947 billion over 2025-20352.
NAPs complement, rather than replace, the NDC-based estimates above. The two documents differ in scope, timeframe and level of detail, and are often prepared at different times and through separate national processes, and therefore their needs estimates may not be directly comparable. NDCs remain the primary source of bottom-up needs in CPI’s approach, given their near-universal coverage across Parties to the Paris Agreement and their coverage of mitigation and, in many cases, adaptation needs.
However, where costed, NAPs can sometimes offer a more detailed view on adaptation needs. As shown below, NDCs and NAPs are equally likely to quantify adaptation needs, with around two-thirds of each doing so, but NAPs more often cost these needs at the project or action level (40% of NAPs reviewed, compared with 32% of NDCs).
Of the 58 countries with costed NAPs, 48 also quantify needs in their NDCs, with around two-thirds costed at the project- or action-level. For nine countries, including Argentina and the United Kingdom, NAPs are the only source of quantified needs for 2025–2035 in our database, covering nearly USD 300 billion not captured by NDCs. Because some NDCs draw on the same costings as their NAPs, the two are presented separately and should not be added together.
It should be noted that adaptation needs are inherently difficult to cost. Needs estimates depend on the level of future warming, what level of resilience is considered sufficient, and when investments are made. Countries use widely varying approaches to estimate them, often listing planned activities rather than assessing what would be needed to address projected climate risks. NDC- and NAP-based figures should therefore be read as what countries have quantified to date, not as a measure of total adaptation needs, which are likely to be substantially higher.
To view NDC- and NAP-based needs for each country, visit our bottom-up needs interactive dashboard.
Limitations in bottom-up Climate finance needs
WHAT DO BOTTOM-UP NEEDS TELL US?
Despite the limitations of current NDCs and NAPs, the bottom-up needs estimates provide insights both on the level of countries’ climate ambition and on their stated capacity for achieving these objectives. With only 12% of EMDE needs expected to be met from domestic sources, and most of the remainder either conditional on international support or unspecified, bottom-up needs estimates illustrate that continued, significant international support is needed to help countries meet their climate targets and avoid the worst impacts of climate change.
Additionally, bottom-up needs estimates reveal that current country-level ambition is insufficient to keep global temperature rises within 1.5°C. While some countries estimate their national climate finance needs using predictive models aligned to a 1.5°C pathway, in most cases, needs stated in NDCs and NAPs are derived from a list of costed mitigation and adaptation measures or projects countries aim to implement. Therefore, the scale and granularity of costed climate finance needs varies widely across NDCs.
Data limitations and variations in methodologies used to derive bottom-up estimates within NDCs result in data gaps, lack of granularity, and inconsistencies across country-level estimates. Where available, NAPs can help fill some of these information gaps for adaptation, but coverage remains incomplete. Broadly, data limitations result in the severe underestimation of needs at the country level. Therefore, significant effort is needed to improve, align, and standardize methodologies for establishing climate targets and estimating the costs of their implementation within NDCs and other national planning documents, alongside enhanced support for countries to more accurately and comprehensively estimate their climate finance needs. Strong NDCs can play a role in sending investment signals to investors and develop into actional roadmaps for climate finance. CPI conducted an analysis examining the strength of investment signals in the first 18 NDCs submitted by non-Annex I parties to the UNFCCC by mid-2025, and found that opportunities exist for strengthened investment signals in forthcoming NDCs.
