Profiles

Fernando Jaramillo Bolin

Fernando Jaramillo

Forskare

View page in English
Arbetar vid Institutionen för naturgeografi
Telefon 08-16 47 71
E-post fernando.jaramillo@natgeo.su.se
Besöksadress Svante Arrhenius väg 8
Rum V 310
Postadress Inst för naturgeografi 106 91 Stockholm

Publikationer

I urval från Stockholms universitets publikationsdatabas
  • 2018. Fernando Jaramillo (et al.). Environmental Research Letters 13 (2)

    The Cienaga Grande de Santa Marta (CGSM) is one of the world's most productive tropical wetlands and one that has witnessed some of the greatest recorded dieback of mangroves. Human-driven loss of hydrologic connectivity by roads, artificial channels and water flow regulation appears to be the reason behind mangrove mortality in this ungauged wetland. In this study, we determined the CGSM's current state of hydrologic connectivity by combining a remote sensing technique, termed as Wetland Interferometric Synthetic Aperture Radar (InSAR), with a hydrologic study of river water discharge. For this research, we processed 29 ALOS-PALSAR acquisitions taken during the period 2007-2011 and generated 66 interferograms that provide information on relative surface water level changes. We found that change in water discharge upstream on the main tributary of the CGSM could explain at most 17% of the variance of the change in water level in the CGSM. Fresh water inputs into the wetland were identified only when the mean daily water discharge in the river exceeded 700m(3) s(-1), which corresponds to only 30% of the days during the period. The interferogram analysis also revealed that artificial channels within the wetland serve as barriers to water flow and contribute to the overall loss in hydrologic connectivity. We recommend increasing fresh water inputs from the Magdalena River by reducing water regulation of fresh water from the river and improving connectivity on either side of the artificial channels crossing the CGSM. This study emphasizes the potential of the application of wetland InSAR to determine hydrologic connectivity in wetlands that are completely or poorly ungauged and to define the necessary guidelines for wetland hydrologic restoration.

  • 2018. Fernando Jaramillo (et al.). Hydrology and Earth System Sciences 22 (1), 567-580

    During the last 6 decades, forest biomass has increased in Sweden mainly due to forest management, with a possible increasing effect on evapotranspiration. However, increasing global CO2 concentrations may also trigger physiological water-saving responses in broadleaf tree species, and to a lesser degree in some needleleaf conifer species, inducing an opposite effect. Additionally, changes in other forest attributes may also affect evapotranspiration. In this study, we aimed to detect the dominating effect(s) of forest change on evapotranspiration by studying changes in the ratio of actual evapotranspiration to precipitation, known as the evaporative ratio, during the period 1961-2012. We first used the Budyko framework of water and energy availability at the basin scale to study the hydroclimatic movements in Budyko space of 65 temperate and boreal basins during this period. We found that movements in Budyko space could not be explained by climatic changes in precipitation and potential evapotranspiration in 60% of these basins, suggesting the existence of other dominant drivers of hydroclimatic change. In both the temperate and boreal basin groups studied, a negative climatic effect on the evaporative ratio was counteracted by a positive residual effect. The positive residual effect occurred along with increasing standing forest biomass in the temperate and boreal basin groups, increasing forest cover in the temperate basin group and no apparent changes in forest species composition in any group. From the three forest attributes, standing forest biomass was the one that could explain most of the variance of the residual effect in both basin groups. These results further suggest that the water-saving response to increasing CO2 in these forests is either negligible or overridden by the opposite effect of the increasing forest biomass. Thus, we conclude that increasing standing forest biomass is the dominant driver of long-term and large-scale evapotranspiration changes in Swedish forests.

  • 2015. Fernando Jaramillo, Georgia Destouni. Science 350 (6265), 1248-1251

    Flow regulation and irrigation alter local freshwater conditions, but their global effects are highly uncertain. We investigated these global effects from 1901 to 2008, using hydroclimatic observations in 100 large hydrological basins. Globally, we find consistent and dominant effects of increasing relative evapotranspiration from both activities, and decreasing temporal runoff variability from flow regulation. The evapotranspiration effect increases the long-term average human consumption of fresh water by 3563 +/- 979 km(3)/year from 1901-1954 to 1955-2008. This increase raises a recent estimate of the current global water footprint of humanity by around 18%, to 10,688 +/- 979 km(3)/year. The results highlight the global impact of local water-use activities and call for their relevant account in Earth system modeling.

  • 2015. Fernando Jaramillo, Georgia Destouni. Science 348 (6240), 1217

    Steffen et al. (Research Articles, 13 February 2015, p. 736) recently assessed current global freshwater use, finding it to be well below a corresponding planetary boundary. However, they ignored recent scientific advances implying that the global consumptive use of freshwater may have already crossed the associated planetary boundary.

  • 2017. Bruce M. Campbell (et al.). Ecology & society 22 (4)

    We explore the role of agriculture in destabilizing the Earth system at the planetary scale, through examining nine planetary boundaries, or safe limits: land-system change, freshwater use, biogeochemical flows, biosphere integrity, climate change, ocean acidification, stratospheric ozone depletion, atmospheric aerosol loading, and introduction of novel entities. Two planetary boundaries have been fully transgressed, i.e., are at high risk, biosphere integrity and biogeochemical flows, and agriculture has been the major driver of the transgression. Three are in a zone of uncertainty i.e., at increasing risk, with agriculture the major driver of two of those, land-system change and freshwater use, and a significant contributor to the third, climate change. Agriculture is also a significant or major contributor to change for many of those planetary boundaries still in the safe zone. To reduce the role of agriculture in transgressing planetary boundaries, many interventions will be needed, including those in broader food systems.

Visa alla publikationer av Fernando Jaramillo vid Stockholms universitet

Senast uppdaterad: 27 maj 2019

Bokmärk och dela Tipsa