Additionally, degraded lands in the NEB are expanding due to increasing firewood production and poor soil management and agriculture practices (slash and burn), which cause deforestation, soil salinization, and ultimately desertification [4; 13]. The rapid intensification of desertification in the NEB is responsible for the suppression of the Caatinga vegetation, a highly biodiverse, exclusively Brazilian seasonally dry tropical forest, characterized mainly by thorny deciduous species [14]. The degradation of the Caatinga biome may play a fundamental role in the formation and expansion of desertification hotspots in the NEB, as previously reported by others [4; 13; 15]. Therefore, it is of extreme significance to study and quantify the impacts of desertification in key environmental and biophysical processes related to the native Caatinga vegetation, such as energy and CO\({}_{2}\) balances. For instance, despite the systematic increase in CO\({}_{2}\) concentrations in the atmosphere throughout the years, terrestrial vegetated ecosystems usually behave as carbon sinks, and thus, biome-oriented studies are of the utmost importance to better understand CO\({}_{2}\) dynamics at the regional and global scales [16; 17]. However, the interannual variability in CO\({}_{2}\) absorption by terrestrial carbon sinks is strongly related to rainfall, temperature, and other meteorological variables [18; 19]. Recent studies showed that the Caatinga biome potentially behaves similar to a carbon sink even in dry years, but CO\({}_{2}\) dynamics were largely driven by meteorological conditions [20; 21]. The potential impacts of desertification in the CO\({}_{2}\) balance of Caatinga are yet unknown. Similarly, the energy balance analysis over vegetated surfaces allows the dimensioning of mass and energy exchanges in the soil-vegetation-atmosphere system through the partitioning of net radiation into energy processes such as latent (associated with evaporation and transpiration processes), sensible (used to heat the air), and soil (which is associated with heat diffusion in the soil) heat fluxes [22; 23; 24]. They also allow the assessment of microclimate changes over a given region due to land-use changes, as well as soil and atmosphere conditions. Therefore, landscape changes due to desertification will impact the partitioning of energy balance [25]. For example, previous studies in the Caatinga biome indicated that 50% of annual net radiation was used as sensible heat flux [24]. The expansion of desertification hotspots can further increase the portion of radiation transformed into sensible heat flux, which may impact the local and regional climate [25]. Currently, there are no studies in the scientific literature with in situ measurements of the components of these balances over desertification hotspots in the NEB, despite the undeniable environmental and social relevance of this process to the region. Thus, the objectives of the present study were (1) to evaluate the role of the different components of energy and CO\({}_{2}\) balances in desertification hotspots in the semiarid NEB and (2) to assess the regional dynamics of the desertification process in relation to meteorological variables measured in situ. The energy balance components (latent and sensible heat fluxes), the Bowen ratio (which is the ratio between sensible and heat fluxes), and the CO\({}_{2}\) balance components (gross primary production--GPP, and net ecosystem exchange--NEE) were simulated using SVAT models. To that end, we used data measured in the Cabrobo site (NEB desertification hotspot) and in the Ibmirim site (surroundings of the Cabrobo desertification hotspot) while also identifying trends in the meteorological variables measured over the two sites. The state-of-the-art method for the evaluation of CO\({}_{2}\) and energy balances over vegetated environments is the use of eddy-covariance systems through high-frequency continuous measurements [26; 27; 28].