NAVIGATING US CLIMATE POLICY UNCERTAINTY: NOVEL EVIDENCE FROM CARBON MARKETS, CRYPTOCURRENCY (DeFi), AND RENEWABLE ENERGY INNOVATIONS

Öz

The aim of this study is to reveal the dynamics between climate policy uncertainty (CPU) and S&P Global Carbon Credit Index (CARBON), S&P Cryptocurrency DeFi Index (DeFi), and WilderHill New Energy Global Innovation Index (NEX) using data from December 2017 to March 2024 in the US. Fourier Bootstrap ARDL, Fourier Bootstrap quantile causality, and KRLS methods are used in the study. The findings reveal that there is a negative relationship between the CARBON and the CPU index in the long term. Although the DeFi does not have a statistically significant effect in the long term, it reveals that it has a negative effect on the CPU index in the short term. In contrast, the NEX has a positive relationship with the CPU index in both the short and long term. Moreover, there is a U-shaped non-linear relationship between the NEX and the CPU index, which weakens in moderate climate uncertainties and strengthens again in high uncertainty. Considering the causality results, there exists a causality from CARBON to CPU in the 2nd, 3rd, and 4th quantiles, and from CPU to CARBON in the 2nd and 3rd quantiles. Additionally, there is a causality from DeFi to CPU in the 8th quantile and from CPU to DeFi in the 1st quantile. Finally, there is a causal relationship from NEX to CPU in the 2nd, 3rd, 4th, and 5th quantiles and from CPU to NEX in the 9th quantile.

Anahtar Kelimeler

• Climate Policy Uncertainty
• Decentralized Finance (DeFi)
• Renewable Energy
• Carbon Credit

Destekleyen Kurum

None

Etik Beyan

The author(s) confirm compliance with the requirements for ethical approval and declare their understanding of the relevant rules and content.

Teşekkür

The author(s) sincerely thank the editorial board and reviewers for their valuable time, insightful feedback, and constructive suggestions, which have significantly contributed to enhancing the quality of this manuscript.

ABD İKLİM POLİTİKASI BELİRSİZLİĞİNİ ANLAMAK: KARBON PİYASALARI, MERKEZİYETSİZ FİNANS (DeFi) VE YENİLENEBİLİR ENERJİ İNOVASYONLARINDAN YENİLİKÇİ KANITLAR

Öz

Bu çalışmanın amacı, ABD’de Aralık 2017 ile Mart 2024 arasındaki verileri kullanarak iklim politikası belirsizliği (CPU) ile S&P Küresel Karbon Kredi Endeksi (CARBON), S&P Kripto Para DeFi Endeksi (DeFi) ve WilderHill Yeni Enerji Küresel İnovasyon Endeksi (NEX) arasındaki dinamikleri ortaya koymaktır. Çalışmada Fourier Bootstrap ARDL, Fourier Bootstrap kantil nedensellik ve KRLS yöntemleri kullanılmıştır. Bulgular, CARBON ile CPU endeksi arasında uzun vadede negatif bir ilişki olduğunu ortaya koymaktadır. DeFi’nin uzun vadede istatistiksel olarak anlamlı bir etkisi olmasa da, kısa vadede CPU endeksi üzerinde negatif bir etkisi olduğunu ortaya koymaktadır. Buna karşılık, NEX’in hem kısa hem de uzun vadede CPU endeksi ile pozitif bir ilişkisi vardır. Ayrıca, NEX ile CPU endeksi arasında ılımlı iklim belirsizliklerinde zayıflayan ve yüksek belirsizlikte tekrar güçlenen U şeklinde doğrusal olmayan bir ilişki vardır. Nedensellik sonuçlarını göz önünde bulundurarak, 2., 3. ve 4. kantillerde CARBON’dan CPU’ya ve 2. ve 3. kantillerde CPU’dan CARBON’a bir nedensellik vardır. Ek olarak, 8. kantilde DeFi’den CPU’ya ve 1. kantilde CPU’dan DeFi’ye bir nedensellik bulunmaktadır. Son olarak, 2., 3., 4. ve 5. kantillerde NEX’ten CPU’ya ve 9. kantilde CPU’dan NEX’e doğru bir nedensellik ilişkisi bulunmaktadır.

Anahtar Kelimeler

• İklim Politika Belirsizliği
• Merkeziyetsiz Finans (DeFi)
• Yenilenebilir Enerji
• Karbon Kredileri

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