For background information, see previous question from Susan Salafsky "What was the global extent of drought conditions during 2001-2003 and how did it affect the biota?"
Southeastern South America (NE Argentina. Southern Brazil, Uruguay, Paraguay and SE Bolivia), more or less the Rio de la Plata watershed, had rainfall above the average during 2001-2003, particularly during 2002 (eg historicalmaximorum in Uruguay). This is conincidient with the moderate El Niño 2001-02. I guess there are other areas where you'll find this pattern.
I do not agree with "Worldwide drought" but extended drought!
Interesting! Drought conditions were observed in United States, Brazil, North China, Algeria, and Ethiopia during 2001-2003. Since southeastern South America had above average rainfall, it appears that the precipitation could have been further south. Hopefully someone with information from areas in the far southern hemisphere (New Zealand/Australia/South Africa) will respond to confirm or contradict this pattern.
I agree it is not a "worldwide drought" but rather a severe and extended drought that was observed in areas across the globe.
USA and Brazil are huge countries. In Brazil El Niño is associated with drought at NE and rainfall at S/SE Brazil. Similarly in USA El Niño is associated with rainfall in the Mississippí watershed and other regions, I like "Severe and extended". Rgds, Gustavo
I do not agree with the "worldwide drought" in 2001-2003 too. However, the lack of precipitation was observed in some regions. Figures of 12-month SPI in additional files can answer to your question.
Thank you for posting the figures Elena. Very interesting! I have some questions regarding the maps:
1) Is the figure order from the top down 2001, 2002, 2003?
2) Is the 12-month index based on the calendar year (January-December) or a biological year (e.g., April-March)?
3) How accurate are the maps compared to local information? For example, the Palmer Drought Severity Index for northern Arizona identified 2004 as a drought year despite record-high precipitation in my study area.
1) of course, the figures ordered from the top of 2001 to bottom of 2003.
2) 12-month SPI for December (from Jan to Dec).
3) SPI reveals drought as a lack of precipitation compared with the local climatic norm. PDSI evaluates the potential evapotranspiration, moisture capacity, groundwater recharge etc. not only in the current period but also takes in account the previous moisture conditions. Therefore SPI and PDSI often show different results.
in the case of Bosnia and Herzegovina (located in Southeast Europe) we can say that years 2000, 2001 and 2003 were drought years and 2002 was not. Here you have different SPI for 2 stations in central B&H (First pic. red means drought more than -2, blue wet spell).
Also, I attached drought magnitude for SPI2 for the same location, and as you can see, for this period (2001-2003) there are more than 5 drought months per year. SPI shows no drought in 2002. A similar situation is in Tuzla (north part of B&H), where self-calibrated Palmer Drought Index (scPDSI) show drought for 2001 and 2003 while 2002 was more or less normal. Soil moisture deficit (in mm) calculated with Palmer water balance and actual AWC, also show same trends.
You are basically asking a global ecology question, although phrased as a drought one. I'd like to add to Elena's contribution by sharing maps for SPI6 from the Global Drought Observatory (European Commission Joint Research Centre). We (Global Drought Information System0 also have maps, but, alas, they are not archived as EDO's excellent maps are. (I've only posted the summer (biased for Northern Hemisphere) season--June, July, August.
This doesn't answer your question, as to where the water went. That question is a global teleconnection issue, in part. 2002-2003 were weak El Nino years, but they had a major impact on Australia (in the Southern Hemisphere). As noted above by Gustavo, you can see the higher recorded precipitation in the La Plata Basin and Argentina.
Cheers!
PS You should not use the Palmer Drought Severity Index; SPI is better. PDSI uses a 19th century Thorntwaite approximation for the water cycle. SPI, also, is only a measure of precipitation deficiency; whether a drought is recorded requires supplemental information, like impact reports if they are available. (If secondary sources of water, like groundwater, are available for irrigation, any drought signature may be masked even if SPI is low to slightly negative).
Thank you for posting the figures Sabrija. I found the extended time series fascinating! I have 2 questions that will help me interpret the plots:
1) Where are the 2 stations in central Bosnia and Herzegovina located? Can you post a map with the plotted locations?
2) Are there elevational differences between the 2 stations?
FYI: I wanted to vote again to promote your quality contribution as this is exactly the type of information I am interested in, but ResearchGate would not let me.
W. Pozzi: Thank you for sharing the maps from the Global Drought Observatory for June, July, and August 2001. Could you please post the June-August maps for 2002 and 2003? Also, if you have access to annual maps could you please post them? I am curious if they show different trends since it appears that the summer season maps do not adequately capture annual variation in precipitation. For example, the 2001 maps you posted indicate average conditions (white) during June-August but, based on data from a weather station within my study area in northern Arizona USA, 2001 was the third driest year during an 80-year period of record. In addition, the maps Elena posted for 2001 indicate above-average precipitation (blue) for parts of Russia, whereas the summer season maps indicate the same general area had predominately below-average precipitation (yellow).
P.S. I used the Palmer Drought Severity Index to identify the relative severity of drought in 2003 (-4.46 was the lowest PDSI value for northern Arizona since 1903). To identify the effects of climatic conditions on the reproductive responses of an apex predator, I primarily used high-resolution spatially explicit monthly precipitation and temperature data from the PRISM Climate Group (www.prism.oregonstate.edu). Please see my dissertation "Reproductive responses of an apex predator to changing climatic conditions in a variable forest environment" for more information.
Dear Susan, I attached the map of Bosnia and Herzegovina, with all the stations that were active and that are still active (public stations, getting climatic data from 1949 until today).
Station Sarajevo (number 122) is at 630 m a.s.l., station Butmir (No. 24) at 518 m a.s.l. and station Tuzla (No. 145) at 305 m a.s.l. As you will see from the map, stations Sarajevo and Butmir are Station Sarajevo (number 122) is at 630 m a.s.l., station Butmir (No. 24) at 518 m a.s.l. and station Tuzla (No. 145) at 305 m a.s.l. As you will see from the map, stations Sarajevo and Butmir are close to each other (about 20 km) jet, they have relatively big differences in drought occurrence and severity (the first pic. in the previous post). Currently, I am working on another paper, where I will analyse drought (drought indices: scPDSI, SPI and SPEI) for more than 20 stations across B&H (all yellow stations on the map).