El Salvador: Learning on evapotranspiration rates in climate change scenarios

On 25-27 September, the Central American Network of Engineering Institutions (REDICA) members were trained on evapotranspiration rates in climate change scenarios. Members learnt to understand and run different tools to determinate the water needs for crops irrigation. The workshop was run in San Salvador city, El Salvador, in collaboration with Cap-Net.

The workshop was facilitated by Lilliana Arrieta Quesada (REDICA), Jose Roberto Duarte (REDICA), Omar Flores  (Universidad de San Carlos de Guatemala), Otoniel Echeverría (Universidad del Valle de Guatemala), and Alejandra Rojas (Universidad de Costa Rica).


Even when the water stress level in Central America is not high as in Western Asia, Central Asia and Northern Africa (where it is over the 60%), the region faces serious water stress levels during parts of the year. For instance, 32% in Mexico, 39% in Dominican Republic and 14% in El Salvador. The reuse of wastewater, desalinated water and direct use of agricultural drainage water are some of the strategies applied to reduce the water stress. Decreasing water abstraction by increasing productivity and efficiency in the use of water resources and increasing its sustainability is crucial. Escalating water efficiency and improving water management are critical to balance the competing and growing water demands from various sectors and users.

The level of water stress is the ratio of total fresh water withdrawn to the total renewable freshwater resources in a country or region, after considering the water needed for sustaining the natural environment. Water stress does not only hinder the sustainability of natural resources, but it also hampers economic and social development, tending to disproportionately affect the most disadvantaged people.

The knowledge on water stress level contributes to adaptation capacities and climate resilience, as well as the mitigation of climate change within agricultural sectors.

Objectives achieved

During the training the participants were able to:

  • Familiarise themselves with the different tools to reduce the risk of drought
  • Differentiate the loss of crops by climate events from the loss of crops triggered by conflicts between countries. This also revealed the need to monitor the political situation of the regional countries.
  • Identify the need to continue training to reduce the limitation on the technological field. A recommendation was made to develop a Unit of Georeference to support small and poor farmers as well as to provide more training for the sub national and national level.
  • Integrate task groups training in tools that helps to identify the evaporation rate of crops in the Central America region.
  • Transfer of knowledge to monitor the compliance of the human right to food with the international standards

Lessons learnt

Participants learnt the basics of the water cycle, Dublin Principles, basin approach, IWRM planning cycle and the carbon cycle. In addition, they studied the human right to food and different methods of monitoring its compliance. Water governance and the components of equity and efficiency in water resources were also part of the training material.

With regards to crops and climate change scenarios, participants learnt about the classification of soil use by satellite picture, the mechanisms of climatological data, evapotranspiration and meteorological factors, the different types of evapotranspiration were explored along with a case study from Panama.

Besides, different agrometeorological systems were studied. For example, “AquaCRop” a single crop model for irrigation, and WaPOR, a tool from FAO that helps to understand the water scarcity rate, the crop water yield, the variability of climate change and the radicular depletion zone.

Finally, participants gained knowledge about the different scenarios of climate change in crops and climate change adaptation.